Hell yes. In clubs and pubs all the time.
I was riding my horse once and a man shouted at me from outside a pub that I was too fat to ride. I am much more confident when I'm riding so I rode over to the pub and asked to talk to him but he wouldn't come out and face me..
A couple in their early twenties whispered to each other at a supermarket checkout, I heard the woman say to her boyfriend 'will you still love me I I look like that' and him saying no - I turned around and told them of they were going to talk about people they shouldn't be so obvious.