I'm in my mid-40s and only recently realised I do this all the time when I'm barefoot/in socks, if I'm standing doing the washing up, brushing my teeth etc. I roll onto the sides of my feet and stand like that. DP says I've done it the whole time he's known me (20y!). I don't do it when I've got shoes on, to the best of my knowledge. Apparently I also jiggle around from side to side when I'm nervous, who knew?!
Now I've noticed I keep catching myself doing it and have to make an effort to stand with my feet flat, which doesn't feel right! Guessing it's not great for my feet/legs...
Does anyone else do this?