What's something that really grinds your gears?

https://sh.itjust.works/post/56493013

People who put their shopping cart on one side of the isle then stand is the other to block it completely.
People who don’t return their trolley
People who park their 2 seater bmw in the family spot while I’m trying to find a safe place to park with my family of 5.
Nah if that spot is open I’m taking it