I think I've satisfied myself (though probably nobody else) that people's tendencies to quit only when they've lost their bankroll doesn't affect the house's percentage profits, and that the current better-than-expected profits are merely the result of some good house luck earlier this year.  Even if that whale was always intending to keep playing until he lost it all, that process could have taken him 10 times longer than it did.  The house profits would be the same as they are now, but they would then be less than expected instead of being more than expected as they currently are.