I can confirm, using the power of science, that THC does not stay in its psychoactive state below a certain temperature. The only way it can is if it binds to something, typically some kind of fat. That's why an edible can get you high days after it was made.

Basically, weed might stink a little more than tobacco but not by much. The only reason you smell someone that stinks of weed is the same reason you smell someone that stinks of cigarettes: they sat in the smoke and it stuck to them.

Having been a stoner for years, I've never once had someone comment on the smell. Sure, I suppose it's possible that literally everyone I know and have potentially interacted with on an olfactory level was just being polite but... I doubt it.