I think questions like this tend to go to the very root of how well we handle being different.
For instance:
I grew up with a disability, which instantly marked me as different from all the other kids. I was also the fat kid. I was one of the smart kids, but I felt I was one of the stupid kids amongst the smart kids. I never had the luxury of being "one of the guys", so for me, being gay was never a problem, because it was simply yet another difference, not a defect.
But for someone who was the Big Man on Campus? A teen beauty queen with a gaggle of friends? The comfort of being one of the crowd or the center of attention can be tremendous, and the prospect of losing that or replacing general approbation with considerable condemnation, particularly within a school setting, may seem too terrifying to risk.
So while I wouldn't consider such a pill because it wouldn't improve my existing problems, I can understand that people who never developed that kind of strength, or from certain family/community environments where homosexuality is considered a monstrosity, wanting such a "cure".