Why can you take back don't pass but not pass bets at craps

Question: Say you bet "pass" or "don't pass" at craps, and it's after the come-out roll. You can take back the "don't pass" bet if you think you'll lose because the shooter will make the point. But you can't take back the "pass" bet if you think you'll lose because the shooter will seven-out. Why one and not the other?

Answer: When you bet on "don't pass," you're the underdog during the come-out and are have the edge thereafter. The odds against you while the shooter is coming out are 8-to-3 but the payoff is only 1-to-1. Subsequently, the payoff remains at 1-to-1 but the odds are for you by 2-to-1, 3-to-2, or 6-to-5 when the point is four or 10, five or nine, or six or eight, respectively. Casinos are happy to let you take down bets on which you're favored.

When you bet on "pass," you're favored during the come-out and the casino has the edge thereafter. The odds for you are 8-to-4 while the shooter is coming out but the payoff is 1-to-1. Subsequently, the payoff remains at 1-to-1 but the odds are against you by 2-to-1, 3-to-2, or 6-to-5 when the point is four or 10, five or nine, or six or eight, respectively. Casinos would be foolish to let you make a bet while you're favored, then take it down when the edge switches to their side.

Incidentally, you can put up or remove "odds" any time after the come-out roll on either of these bets. The reason is that there's no edge associated with the "odds." Although a bet with no edge is attractive to the player, it makes no difference to the casino's bottom line when averaged over the long term.