Clock Game has a bonus because of the fact that before the bonus, even if you played for two maximum-prized prices (for this game), a contestant could win only $1,998. The $1,000 bonus was added to bring Clock Game's prize package into the 21st century. Now, while I'd like to see them go to the system they used on the 1986 specials (envelopes with different amounts), that's for another time and place...
That's certainly not the same as offering someone a $14,000-$18,000 car, then giving them the possibility of taking home another $10,000 on top of that - even if they manage to blow both grocery items. As I said before, if there was only one car space on each cube, maybe (and, if so, NOT as much as $10,000), but not with three on each cube.. The odds are obviously far better than doing so in Yahtzee. Plus, it's not like they play Let 'Em Roll for a gas pump replica or the like, either... That is, after all, a new car they are playing for.