Serious question: what in the actual hell is up with hating on the mangakas?

I see a certain few users around here who just spread hate, and it's pathetic. Just because you don't agree with what a mangaka has done in their work, doesn't give you the right to act like an #sshole. The only ones I'll hate on would be those who are actually terrible people, like Watsuki, but besides that, it's stupid to act so childish just because they did something you don't agree with. Seriously, it's disgusting to see.