So let's say we have a man in the same rec room. He whips out a tube of moisturiser and rubs it into his face. And then he gets out some beard oil and meticulously applies it to his facial hair.
OK to do in the rec room or would you expect him to carry out that type of grooming in the bathroom?
Personally, I fall into the latter group. I'd expect him to use the bathroom - as I'd expect a woman to use the bathroom to freshen up makeup.
As a society we operate by a set of agreed social rules and etiquette, and grooming is traditionally been something that etiquette suggests is done in private. It's considered to be bad manners/bad etiquette to get out a compact and apply makeup while in company.
So there's nothing "wrong" with doing your makeup in public, but it seems a bit rude imo. I'd feel extremely awkward if a friend or colleague was doing their makeup sat next to me in public. It's quite a personal act and it's disconcerting if someone is doing it right in front of you.
Also, as you brought the subject up, yes, it does look a bit vain. If everyone is sat there together and you're peering into a mirror to apply more mascara or concealer, then it does look a bit conceited. Do you never use the toilet during the day? Surely you can freshen up your makeup then? And also, who needs to freshen up mascara halfway through the day?! Needing to touch up mascara or concealer after a couple of hours suggests a bit of an unhealthy obsession with appearance.
Having consideration for manners and social "rules" isn't misogynistic.
If you feel comfortable applying makeup in the rec room and don't care what colleagues think then that's fine. It's not an outrageous act. But as this thread shows, plenty of people will feel a bit icky about it. And you might get a reputation as someone who's a bit vain. We all make judgement calls about other people, even on an subconscious level. If you're not bothered, then carry on and address any comments as you see fit.