They hate him because THEY CANT HANDLE his FLAWLESSNESS. Lina said it herself, he commands attention simply by BEING. And I think they are worried that they can smell the winners CASH on him.
Girl, YES. You could SMELL the envy on those three as they mocked Ryan in the treehouse. They criticise Ryan and Dave for isolating themselves from the group when in reality they're pressed because they know he just doesn't want to suffer their foolishness.