I don't know how anyone can find good reason to hate Pacquiao. I am not a big fan, but I always appreciated him in his prime. His story coming up is very inspirational.
It's not pacman himself. But the hate is more on his stans. I'm Filipino myself, a pacman fan, but even I can't stand my own friends and family when I watch boxing! Any none Pacquaio fight, I'll always hear how pacquiao could have knocked out a random boxer quicker. That mayweather Ortiz fight in my friend's house, oh my... Right after that head butt, when mayweather sucker punched him... They were just crying up a storm on how unsportsmanlike mayweather was completely ignoring the headbutts prior to that.