DEAR MISS MANNERS: Is there a correct way for a customer to act at the checkout counter?

I usually stay silent, except to answer and return pleasantries if the cashier offers them. I occasionally glance at the total and assist in bagging if the cashier is alone. I have had similarly quiet cashiers; often, the only exchange during the whole process is "Have a nice day" and "Thanks, you too."

I work in retail myself, and I despise the empty cheeriness and how draining it can be during a long shift. So I figure that giving the cashier a quiet respite is not unwelcome.

I also glance around rather than watch their work, because no one wants to feel like they're being observed or judged. Additionally, I am an introvert and quite shy, so quiet checkouts benefit me, as well. Is this impolite?

GENTLE READER: Brief chattiness between customer and clerk can be charming or intrusive, depending on the people and what is said. Many regular customers enjoy being recognized with a few friendly words where they shop.

Unfortunately, some businesses have discovered this, and mandated forced conversation. It is obvious when this is scripted or required of strangers. Current cliches such as "What are you planning for the rest of the day?" are nosy and annoying.

So Miss Manners agrees that your confining yourself to minimally polite remarks may be as much of a relief to the cashier as it is to you.

DEAR MISS MANNERS: Is it ever OK to use poor etiquette intentionally?

When my sister married someone who already had a child, I went out of my way to include the child at holidays and remember her birthday. I sent her many gifts, but never once got a thank-you or even an acknowledgment that she had received them.

Now that she's an adult, I have sent her wedding shower gifts (I live very far away and didn't attend the event), and still never received a thank-you. I have now received an invitation to her wedding, even though I had told my sister not to invite me as I knew I could not attend. Space is limited, so I suspected the bride would rather invite someone she actually knows, anyway.

Out of obligation, I went to the website for the wedding registry, and there was not a single gift that cost less than $350. I decided that I was not spending that much money on a person who hasn't ever bothered to acknowledge or thank me for any gift I have ever given her. In fact, I decided I was not sending a gift at all.

I know it is impolite, but I don't care anymore. Is this behavior of mine justifiable?

GENTLE READER: While she will never countenance poor etiquette (also known as rudeness), Miss Manners can relieve you of buying yet another present for your niece, who is evidently not grateful to receive them.

You will be astonished to hear that, contrary to almost universal belief, a wedding invitation is not a bill. Presents are voluntary, although it is thought that if you care enough about the couple to attend the wedding, you will want to send them a remembrance.

Understandably, you do not. So don't.

(Please send your questions to Miss Manners at her website, www.missmanners.com; to her email, dearmissmanners@gmail.com; or through postal mail to Miss Manners, Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO 64106.)

DEAR MISS MANNERS: Here is an issue for our times: I was in a coffee bar recently, and a person sitting a few feet away from me was listening to some sort of recorded content on his mobile phone without the benefit of headphones. It was annoying, particularly on top of the shop's programmed music and other face-to-face conversations taking place.

After a while, I asked, in a very polite and civil manner, "Sir, do you happen to have earbuds or headphones that you could use?" He bristled slightly and said that he didn't realize the sound was annoying, then simply shut the device off, for which I thanked him.

Is what I did within the bounds of reasonable and polite behavior? While I would never question someone's right to engage in a face-to-face conversation or telephone call in this situation, my feeling is that playing anything loud enough for someone else to hear amounts to forcing your choice on others, and is therefore inconsiderate. I would appreciate your thoughts on the issue.

GENTLE READER: Certainly this is rude. Bristle as this young man might, you did nothing wrong by politely and reasonably asking him to use headphones in a public place. In fact, Miss Manners assures you, you likely saved him from a ruder patron's much more indignant objections.

DEAR MISS MANNERS: My closest friend has been helping a healthy 92-year-old man clear possessions from his house over the course of a year, beginning after the great loss of his wife. He has given my friend a number of personal items.

Over this time, my friend has mentioned me as a very dear friend, and the man he is helping is inclined to share a piece of jewelry with me. It is a vintage designer piece -- a choker, I believe. I am happy to receive it as a loving response to his loss.

I will likely see photos of the jewelry before actually receiving it -- or even meeting him. Should I acknowledge and thank him before receiving the piece of jewelry? And I would imagine I should formally thank him again after receiving and wearing it.

I believe there is no protocol for the preemptive acknowledgment of a gift. It will be at least three months before I receive it, after he has placed it in my friend's hands to deliver to me. I am a most sincere and constant writer of formal thank-you notes, so you might understand my dilemma.

GENTLE READER: No one ever complained about too many thank-you letters. Well, only if they were bemoaning their own deficiencies in writing them, of course. And fortunately, you do not complain about that.

Miss Manners therefore thinks it would be charming for you to write a letter to your friend's friend, introducing yourself and telling him how honored you are to be the recipient of a piece of his departed wife's jewelry. Then, when you finally receive the gift, you could write another (shorter) letter, acknowledging receipt and saying that it is even more beautiful in person.

There is no reason not to give this kind gentleman some good reading material in exchange for his generosity.

(Please send your questions to Miss Manners at her website, www.missmanners.com; to her email, dearmissmanners@gmail.com; or through postal mail to Miss Manners, Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO 64106.)

DEAR MISS MANNERS: The pandemic has altered life in many ways, perhaps permanently. One change that is grating on my nerves is basic telephone courtesy.

With so many of us working from home, it is now common to be on a business call while listening to dogs barking, babies crying or dishes being washed in the background. One person I work with seems to call me only while she is munching on her lunch. I suppose these callers aren't aware of how distracting these sounds are.

I had to ask one client to call back when he was through at the gym because the sound of someone doing reps on a machine was so off-putting: wheeze, grunt, bang, wheeze, grunt, bang -- constantly repeating in the background. He was cool about it, but was I out of line? Are we supposed to accept this inconsideration as the new normal?

GENTLE READER: Lunch munching and gym wheezing are indeed extremes. ("Lunch Munching and Gym Wheezing" would also be an excellent name for a cartoon show.)

But, Miss Manners points out, none of us is exempt from the occasional barking dog or wayward car alarm when we are working from home, even if the sound is from across the street. She therefore suggests a simple, non-accusatory, "Why don't I call you back at a better time?" And then hope like mad that there is one.

DEAR MISS MANNERS: I have a co-worker who is obsessed with a particular movie series that came out when they were younger. They love to talk about it, which is fine. I have seen them get very defensive, even a bit angry, when someone said they didn't care for the series.

When I was asked the other day for my opinion, I avoided the topic, because I personally do not like the movies. We work at a small company, and it can be obvious when avoiding just one person. How do I best tell them that I'm not interested in that subject?

GENTLE READER: "If you don't want to hear my opinion, then you probably shouldn't ask."

DEAR MISS MANNERS: My nephew is getting married soon. I received the wedding invitation, and it says "vegetarian or vegan with special dietary request." My nephew's family are all meat eaters; none are vegetarian or vegan. I found it odd. Usually vegetarian/vegan options are special request.

Do I mention it? Or is meat a special dietary request? It's a new world, so I wasn't sure.

I was thinking that I would just go along with it and eat a big lunch beforehand. His grandma thought it was funny.

GENTLE READER: Grandma would find it even funnier if you penciled in that your special dietary request was meat.

But your hosts will not be so amused. Miss Manners suggests that you and Grandma therefore make plans to eat your big ol' slab o' cow beforehand or afterwards -- and keep the humor of the whole situation to yourselves.

(Please send your questions to Miss Manners at her website, www.missmanners.com; to her email, dearmissmanners@gmail.com; or through postal mail to Miss Manners, Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO 64106.)