That's a good point. I know the guys I live near hate any kind of flaming gay behavior. They say it makes all of them look bad.
But it is true we do not stigmatize all straight men when stupid fraternity boys date rape women. We can differentiate mature behavior from immature. I hope we can do that with other groups.
Actually, we stigmatize all Frat Boys. And all Nascar fans. It's a subset, but it's the same thing.