What is something that most people normally do that you find weird?

A lot of people kiss their pets or non-human animals in general. I find that very weird. I understand that it is a sign of affection but it seems so off. One reason is that I doubt whether animals really understand this. Also it seems to be on a level of intimacy to me that I find weird sharing with a pet. Not necessarily romantically or sexually (that would be even more weird and wrong and probably illegal). But it is still "more". I am not sure whether I can really explain why exactly I find that weird.

Anyway, what is something that is weird to you but not to most other people?