Oh, yes - buses! Those people who plonk their bag on the seat next to them, and pretend to be too engrossed in their phones to see other people standing. Most of whom for some reason won't ask them to move their bag.
I have no such scruples.
People (usually young, and active enough when getting on and off) who plonk themselves straight in the disabled/elderly seats, when there are plenty of seats elsewhere, plonk their bag on the outside seat, and again pretend to be too engrossed in their phones to notice the old person with a stick, who doesn't like to ask them to move their bag.
I have been known more than once to do it for them.
People who drop litter at bus stops when there's a bin two paces away. Grrr! I often pick it up, and do get some very funny looks.
People who aren't American, who say 'do the math'.
It's mathS!
Could probably go on all day, but it's high time to go and do something useful.