Nah. Not a safety requirement. I just appreciated just sturdy they were and eventually got used to the added weight.

I’m not sure, I’ve been wearing those sorts of boots for quite awhile now and I don’t feel cold in them.

I did try one on quickly and it was ok but it was o my for a quick moment and the front of the boot sort of curls up a little I noticed.

Not sure how warm they would get after awhile of wearing them though.