Well, I have pets who drag toys into walkways where it's easy to step on. I also have atypical proportions and it's a challenge not to accidentally kick a table or chair leg dodging said pets or their toys.

Furthermore, I don't want to make people look at my feet and just socks wears down the socks/can be slippery. Socks also don't shield my feet from spills or things being dropped on them.