yeah. good thing their billions are safe. i was really worried there for a second.
To me it's more about the integrity of the game. If a player is going to take himself out of games to help gamblers win prop bets, then he's potentially affecting the outcome. Sure, a two-way player usually won't see much run so the affect is probably small, but you need a rule to discourage anybody from crossing this line. Fake injuries, point shaving, intentionally missing shots, throwing games... they're all in the same realm.
I'm curious how the NBA will handle the inevitable case of NBA players betting on their own team (or worse, against their own team).