Today's Pet Peeve is about people that arrive late at an event and go right to their seat without checking to see if they are blocking someones view. You know at a hockey game it is common courtesy to wait for a stoppage in play before you go to your seat. Or even when they get there they are in conversation and take a longer than normal time to get into their seat. Instead the stoppage is over and they are still blocking someones view. One time at a hockey game we had a man stand in front of us and blocked our view. When asked to move he said he could stand there as he had a standing room ticket. Yea..... But that doesn't mean standing in front of someone else.
Or maybe even in a theatre they arrive late and look for a seat while they are standing in front of someone . Instead of standing at the back scouting out a seat and then going with out too much disruption to that seat.
One other common courtesy is in Church when someone arrives late and tries to find a seat in the middle of a prayer.
I'm sure you can think of others too but it all boils down to just being polite and not doing something that will interfere with someone else's view or enjoyment of the event. Do unto others what you would want done unto you. You get the idea.