2 reasons for hatred against Oscar:
1. Money
2. Power

He can make the fights "he" wants, and he will get his way, regardless of what the boxing public wants. It's the same reason why we don't have a unified Heavyweight champ, but It's Don King in that division. Others are more worthy at a shot at Floyd, who IS THE P4P CHAMP, but because Oscar wants, he gets, because of the 2 reasons stated above.