I don't think it really matters. I believe what is more important is to ask ourselves why we find it so "offensive" for a man to be "swishy" or "effeminate." I think a lot of gay men find it difficult to deal with effeminate gay guys because they think that str8 people think that ALL gay men are effeminate and therefore "not manly." What is really unfortunate about this way of thinking is it gives credence to the archaic notion that gender is biological. Gender and gender expression are not based in biology.
What do I mean by all this? The fact that you had issues with these supposed "effeminate" men in the restaurant "openly" acting flamboyantly says more about your insecurities about how people perceive you as a gay man. I don't mean to say this to you in a mean-spirited way, and I hope you do not take it as such. There are always going to be ignorant assholes who believe that all groups are one way or another; there's nothing you can do to stop that except to be yourself and prove them wrong.
As for the effeminate gay dudes, consider our world that much richer for having people in it who defy definition, labels, and boxes. Next time, send them a martini and tell them to keep the flame burning bright!