I think 4% of the WSOP main event pool is taken out for the dealers.
There was a bit of a fuss last year when one of the final tables finishers (Andy Black?) got some stick in some quarters because he didn't leave any money behind when he collected his million dollars. The player made the very valid point that the 4% deduction meant he had actually already tipped the dealers over $25,000.
Andy was pretty peed off with the organisors over a couple of issues, so I'm not surprised.
They with held a portion of his prize money for the IRS, despite him being Irish (US players tax is deducted there and then).....then there was the other situation when some guy had not returned from dinner (having receiving incorrect info from organisors) Andy wanted the table to sit out and wait for the guy to return, but organisors insisted the empty stach was to be check/folded and so lost an hours worth of blinds, which were huge at this stage.