In your Martingale example, the table maximum would most likely be set around $2000. So if you lose 6 times (on your $50, $100, $200, $400, $800, and $1600 bet

In your Martingale example, the table maximum would most likely be set around $2000. So if you lose 6 times (on your $50, $100, $200, $400, $800, and $1600 bets), you can't double your bet anymore. You'll be stuck with betting $2000 at most, which means you can longer guarantee yourself a profit. But now that I think about it, you could always just move to another table with a higher limit. Of course, if you're going through all this trouble to make $50, you probably don't have the bankroll to keep going. Maybe another reason for tables having different limits is that the pit bosses don't trust the dealers (or security?) in the low-roller areas to handle money above a certain amount?