That is the reason why I stay out of the Apple discussion area. But I don't think the term is an insult if you have a group of people that won't listen to reason.
Is calling someone "fat" ok if that person is actually fat? Is calling someone "stupid" ok if the person is stupid?
A Fanboy that just stirs the pot is just as much a troll in my book.
Not if they're only giving their opinion. A lot of new users truly think Apple can do no wrong and argue accordingly. It's still their opinion and they have a right to it, it doesn't matter how annoying you might think it is.
And again, what does calling them "fanboys" accomplish other then stirring the pot even more?