McMurphy unkownly allienates Billy Bibbit after the meeting is over. How? And How does this work into Ratchedś plan?

Billy is the only one who openly defends McMurphy, but after the meeting McMurphy asks Billy for money for Candy’s visit. Billy, who idolizes McMurphy, begins to think that Ratched might be right about McMurphy trying to financially take advantage of the others in the ward.