I usually have some kind of food with me (nuts or trail mix) that I will periodically snack on during long tournament games, and I have never had an opponent object or seem in the least bit annoyed. I suppose the kind of food could make a difference, but I honestly don't see the issue here.

Snacking during chess games has a long history among world champions. Many consider it essential for maintaining optimal performance.

Didnt someone wear earphones in the US Open once and they withheld his prize because they felt moves were being transmitted to him?

Personally I dont really see the big fuss. If I thought someone was cheating then yes I'd complain. If I thought it might annoy them then maybe again.......

Earplugs are fine IMO as is snacking. I might find it amusing if someone sat down with a takeaway in front of me but it wouldnt particularly bother me. There are way more devious tricks some players have in their arsenal than that and it's up to us to protect ourselves against them.

As a slight deviation - many players get up and wander whilst it's your move. Would you feel upset if you saw them chatting to a seriously stronger player during such a wander?

I frequently wear earplug style headphones (like the ones you wear when shooting a gun) because I am easily distracted/annoyed by sounds. I have played tournament games with a wedding reception dance party in the same room (big hotel conference room with portable wall divider separating us), and I've played with the pairings and standings posted on the wall right over my head where I was sitting at my table, and the door to the room (which squeaked) was also right behind me. I played two of the worst games of my life in those conditions because I was annoyed the whole time. Since then, I always have the headphones with me.

I don't wear them constantly, though. When I feel like I need to concentrate extra hard, or something in the room starts to make noise, I just slip them on. I had them on and got up to walk around once (forget I was wearing them), and the TD came over to me and motioned for me to hand him the headphones. He slipped them over his ears and smiled and said "I just wanted to make sure I didn't hear some Russian guy talking about openings." He was joking of course, but he was definitely serious about checking them. I didn't mind, obviously.

By the way, these headphones do not have any ability to play sounds at all--no cords, nothing like that. I would be against people being able to wear that type of headphones in a game.

I don't eat during a game. I usually eat a meal either before a game or after one before the next round, so I'm never really hungry. I also don't mind if people eat while playing, whether it's a small snack or a large meal. It's not that distracting to me, and if my opponent wants to try to eat something big while playing, more power to him. It's definitely going to distract him more than it is me.

Is it ok to stir your coffee with a rook before placing it back on h1?

Only if you lick the rook dry before placing it back.

Sounds like a slightly messier-than-normal rook lift.

Lol I thought this was a level.
Never seen anyone wear headphones during a chess game. Never thought this would be acceptable anywere.

I always stand up to eat a sandwich but finish it at my board when my opponent makes a move. Don't care much what other players do but I usually find it impolite to start eating at the board.

I have no problem with the other side of the board eating during a game, especially if they share . I can see where it would be annoying to some people and where there might be problems (I mean, where do you put the plate when there is usually barebly enough room for the board and paper to record moves?). Earphones and headsets don't even bother me. I mean, if you're willing to cheat to beat a patzer like me then what's the point of even playing in the first place?

That said, it'll be a cold day in Hell before I sit down to play a game and not be allowed to have my cup of coffee at my side.

I eat at the board all the time. I keep napkins handy to thoroughly wipe my hands before touching any pieces.

When organizers stop giving us 30 minute lunch breaks with no food nearby, I'll stop bringing it back

Last year during the final rounds of our national team champs coffee cups weren't allowed in the playing hall since the players would mess up the felt of bridge tables we were using. oh the amount of grumbling

GM Jussupow considered giving up chess some years ago when, due to the doping tests, there were rumours that you coudn't have more than 5 cups of coffee per game.

I don't see a problem with headphones as long as they're earbuds or completely over the ear so they aren't loud. Obv there are issues with cheating but, I dno, that is a separate issue vs. the etiquette of wearing headphones.

Come to think of it, I'm almost surely going to try and listen to music if I ever play in another actual tournament. Almost always I get bored or my mind doesn't want to focus anymore and I really just want to quit the game and go look at random games in progress b/c I'm bored with mine. This would help immensely from an enjoyment perspective - thanks ookook!