Um, actually, I'm an NYU student and I don't agree with the statement that groups at NYU would have a problem, I know at least that my sorority wouldn't care. I also know that there were rumors that another sorority had a pretty large amount of gay women, some of whom dated eachother, but as far as I know nobody cared. NYU just has too many people to really care or know that much about greek life anyways, so worries about reputation wouldn't really matter. I think maybe some of the fraternities might have caused problems about it, some of them have members that were a bit on the machismo side. At any rate, it's a ridiculous attitude to have towards potential members anyway on a campus where the first question you ask about a cute guy (or girl) you're interested in is whether he's straight(and the answer is often no)!
***Edited to add: Our advisor was also a huge idiot, so I'm not surprised that she would have thrown a fit about something like that***