I get called "sir" all the time. Even while wearing pink shirts and big earrings and my "assets" clearly displayed and my kid hanging off my arm saying: Mom Mom Mom can I get that? MOm MOM! Long hair, short hair.... "sir." I have a huge butt, big boobs, wear make-up almost all the time, earrings, nosering, usually feminine clothes, but once or twice a month I get called sir.
(a couple months ago someone assumed I was my son's older brother)

But when my hair was an inch long, no-one called me sir.

Go figure!