Today during a training at work I had a surreal moment.
There were four people in the room, sitting on couches around a small coffee table laden with snacks. It was, basically, a pretty informal setting.
Getting comfortable, I noticed that the best way to sit on the old and awkward couch was with my feet tucked up under me.
Then I realized it's rude to put your shoes on the furniture. So I decided to take them off.
Then I realized it's probably rude to take your shoes off during a work meeting, even if it's pretty informal as work meetings go.
So I asked if everyone was comfortable with me taking off my shoes.
One person seemed pretty uncomfortable with the idea, and said the same.
I explained my reasoning and she relaxed a little, but probably still didn't want me to take my shoes off. I just said I'd go ahead and not put my feet on the couch. Even though it was less comfortable that way. I didn't say that last part.
Anyway, a few minutes later I noticed she was wearing flip-flops. I could basically see her whole naked feet. Even if I had taken my shoes off, my feet would have been completely covered by my socks.
So clearly foot nudity level wasn't the issue. What was? I certainly don't know.
tl;dr social conventions make no fucking sense.