The “sticky” bonus is becoming more common. Casinos will offer you a 100% match, but will deduct the bonus from the first withdrawal you make (most will simply keep the bonus amount, but some revert it back to your account).
These bonuses can be pretty lucrative… IF you know how to play them.
The most common type of sticky bonus is the loan. The casino will give you “free” chips when you deposit, and then rudely rip them away when you withdraw. The normal strategy (deposit, play a lot of blackjack and or video poker, withdraw) will result in you making a loss (on average).