Someone called my friend old and he's only 30?

IIN?

I guess my friend has a little grey in his hair and he started to go grey in his early 20s. He is 30. I'm 26 so just a few years younger. We're at a bar (he's gay so we weren't on a date) and this couple are sat there in their early twenties maybe? It's hard to tell but I'm thinking 22 years oldish.

Anyway, my friend accidentally knocks over his own beer and it spills A LITTLE onto their area where they're seated at the bar. The girl turns to him and goes, "WATCH IT OLD MAN" and my friend apologizes and says "I'm sorry, it was an accident" and cleans it up. Then her boyfriend said something like, "did the old dude get anything on your dress babe?"

And I was pissed because I'm only a few years younger than him and I'm thinking if they call him old, they're calling me old. So I said "you want to call me old too?" and they said "why would we do that?" and I said "I'm the same age as him (slight lie, okay)" and they just shook their head and the girl said "no b*tch, that's okay, i'll be nice" Then when they left, the boyfriend said to my friend, "don't stay out too late or the nursing home will worry"

is it normal to call people old at 30?