Weed, alcohol, other drugs and Bar stories. I do not partake, but due to it being common amung my peers it is hard to avoid. To them that thing they experienced at that one bar 4 weeks ago is the funniest thing, but I cannot relate at all and its kinda frustrating because I do not intend to partake in such activities just to keep up socially. Same with smoke breaks.
A lot more. On other platforms with more users I always feel like I am just commenting into the void on a post with, idk 400 comments / replies. If it only has 0 to ~150 comments it feels less so.