What are the reasons for discrimination against gays? REA DETAILS, please. :)?

The big reason. Religion, plain and simple. Homosexuality is a sin according to the bible, and most of America follows the christian religion. Some still try to be accepting, but it's hard when the holy text flat out condemns it. That's how you get to the bend over backward stances like "love the sinner, hate the sin."

"Reasons" implies that discrimination is "reasonable", which it isn't. I think it mainly goes on because of self-righteousness and a prurient interest in other people's sex lives held by moral conservatives.

one reason is because in the christan culture it started out with adam and eve so a man in a women and i don't want to generalize but most Christan's who like go to church etc. are against gays because it started as a man and a women not 2 men or 2 woman so yea im christan but i think they should have the same rights i mean we're all people.

I would think its due to the fact that there are a lot of duschbags, I had a class full of people like that who where so religious when it came to homosexuality but then for nothing else. Its also the fact that the US has a lot of people who are so Religious that they have to use their Religion as a shield, its personal discomfort at best, they don't like the idea of 2 men due to how they view things, and how they think others view things in that perspective. Simply its discomfort over something and fear that they might try to "convert" them. Also its worth noting that many people who HATE people of a sexual orientation other than straight are in fact themselves homosexual, they are so hateful to cover this up, and if you get people saying they hate gays and that they are straight then they are probably lying to cover up that they themselves are in fact gay. ^^

Because most americans are very closed minded oh,lady who said something about reproduction.I totally agree.Plus it makes no sense.I mean,many men and woman cannot have biological kids.So,why can they adopt and we can't?

Basically it's because of a long past of persecution, it's been an extreme taboo up until recently. People who discriminate can't put themselves into other people's shoes. They really don't have much empathy, so they don't even relate themselves to the other person. Suddenly the person that they're discriminating against just becomes a part of a routine, they don't think about how they're effecting another human being, they think about how they're effecting "a gay". It's terrible, but it's been repeating in history for as long as two groups of people have disagreed. It takes time for people to change their minds, since a lot of our opinions are given to us by our environment. Even if the country is changing, it's changing slowly. If you try to change it too fast, something will snap, something will break. You have to take things slowly, like sculpting, and morph it into a more favorable shape. I don't think society will ever be perfect, because that would require people to be perfect.

The "WHY WON'T YOU LISTEN TO ME, RABBITS HAVE HOOVES DAMMIT!" Bible says it's bad, and... That's pretty damn well all of it.

It's because people are too deeply rooted in their old beliefs their parents and society bestow upon them.

It was Adam and Eve, not Adam and Steve! This is SOOO not my opinion on gay marriage!, but I thought it was kinda funny :)