The Romans had Opinions on trousers, but the Vindolanda tablets show that people on Hadrian's Wall, at least, wore socks. Not that you'd believe that socks existed from the costume of most Roman re-enactors.

Having struggled with going to the toilet while wearing a shift and a floor-length medieval-style dress on a VERY wet day, I can say from experience that this, too, is very chilly. Having six inches of sodden hem brushing against your bare bottom on a freezing cold day is not at all nice!

I always get particularly bothered with breaches of Data Protection rules in movies - e.g. when a character walks into some institution and, merely by asking, is given the full contact details of one of their customers.