I can't deny that it can be used while frothing at the mouth, but the hyperbolic and insultive usage of the term is not its only usage, just like not all Christians are being hyperbolic or insultive when they describe a group as "sinners". Both labels can be matters of disagreement, to be sure, but both are still relatively fair and benign from one's own perspective. It doesn't matter how nice or respectable a person is, sin is sin and bigotry is bigotry, as defined by the groups who use the terms. I'm not going to quit using the term "bigot" anymore than I'd expect a Christian to quit using the term "sinner."

Same thing with "hateful," really. Granted, we poorly use it sometimes to paint a group as Naziesque, when really the two levels of hate in no way compare. If you are decrying that usage, then you are certainly correct. But realize that it is even more often used in a more clinical way, to describe how social conservatives tend to see us as a "them" to be excluded. That is hateful; it just isn't frothing at the mouth hateful. And when a part of gay subculture is excluding straight people in the same sort of way, you should certainly call them out for it. (And yes, I am sure if you look hard enough you could find someone using the term "bigot" in a truly hateful way -- to tag that person as a "them" to be excluded. But I don't think that is at all the common usage of it.)