The only thing that would make one insecure of course is that they are at an art museum, which is not a 'man' place unless you have been dragged their by your gf/wife.
The whole concept is innane. If I'm walking around with a friend of mine and someone thinks we are gay, I couldn't give a crap.
I might be going out to meet a male friend at a bday party tonight, I sure hope no one thinks I'm gay since my wife isn't going
Even odder, I didn't know this was an 'issue'. I've never heard it brought up before, ever.