Is that perhaps because the straight majority isn't in your face announcing their sexual preference and habits? Could it be that you don't notice how many are normal because we're not demanding your open approval?
I expect it may not be more than 2%, at least openly, in the heartland in part because so many move to the major cities—and so that number seems right to many Freepers, but for those of us in blue-state cities the percentages are much different.