So now I sound like something you order when you're starving and pop in to Burger King for some lunch.
According to this article
70 percent of heterosexual adults in the survey admitted that they knew someone who is either gay, lesbian, bisexual or transgender.
It would be much more interesting if someone would do a survey of a large proportion of GLBT's to see if they knew any straight people. However I cannot come up with an enticing abbreviation for such people that is anywhere near anything resembling a McDonalds menu.