One must just accept that the best one can do is educate the players so they know what is customary. The kind ones will do the right thing. And nothing you say to the cheap ones will change their mind. They are simply justifying their decision to save money at others' expense. And of course a surly or unpleasant dealer need not be overly rewarded. I once played at Luxor where the dealer made such a nasty comment I didn't want to tip him. In fact I didn't (but that's because as usual I couldn't win a hand!)

And it is completely up to the player so one must grin and bear it and hope that generally the generous players' tips will even it out in the long run.

As for me, I don't want to sit there knowing the dealer is cursing me in his head. Bad karma!