Why do Pac and Mayweather get so much hate

I also have to question anyone that says Pacquaio fighting Margarito at 150 was an easy fight for him. Ignoring the fact that Margarito is so much bigger then Pac, Margarito brings on so much pressure it takes certain kinds of fighters to beat him. Pac, being as small as he was, being able to keep Margarito off of him and fight those whole 12 rounds was impressive. If you think otherwise, then I don't know why you even watch boxing.