Ugh I hate when girls do them,girls are fawking evil.
They think saying **** like "SHut the **** up" AS LOUD AS POSSIBLE and then giggling afterwards makes it a neg hit.It's like the find the most embarassing thing to point out about you and saying it in a joking voice makes it okay or funny.
Puerto Rican girls I noticed think doing **** like that is attactrive.
I just look at them like...

and go on my way.
I think girls that do that are nerds who aren't used to being hit on or just flat jealous(usually it's a fine girl you're just not into for whatever reason who blurts out something crazy just to say something).
To answer the question I don't respond if it sounds "mean" cuz intentionally or unintetionally that's not someone you want to be with.