what was something you did and thought was normal until you got a roommate?

Leaving the sponge soaking in the sink. Seriously, I grew up thinking that was just how you kept it ready for the next wash, but my first roommate back in my mid-twenties acted like I was committing a crime against hygiene. Apparently, letting it sit in a pool of dirty dishwater makes it a breeding ground for bacteria. I still think it's overkill, but I’ve learned to wring it out and leave it on the edge of the sink just to keep the peace.

Another thing was the way I handled the trash. I used to pack it down really tight to fit more in so I wouldn't have to take the bag out as often. My roommate lost it one day when they went to throw something away and the bag ripped because I’d stuffed it to the point of exploding. Now I just take it out when it’s full, which is probably the adult way to handle it, but it still feels like I'm wasting perfectly good bin space.