GTBets is very simple. They want you to deposit $200-$300 a week, lose it and repeat. They literally see it as an insult to withdraw. They look at it as they are providing you a service and you need to pay for that service.
They literally want their terms and conditions to read "for entertainment purposes only withdrawals not permitted" They obviously can't do this so they do the next best thing. Have small limits, very limited withdrawal options, large roll overs on bonuses and even smaller limits on wagers that go towards bonus requirements.
I made a deposit there once and never returned once i looked closer at their limits and withdrawal options. They are a shitty version of Bovada. At lest when Bovada has had enough of you they allow you to withdraw your balance and send it quickly through your preferred method before kicking you out the door. GTBets will empty your pockets first apparently.