The biggest advantage of gambling with Bitcoin is that it is private and tax free. The government cannot benefit from your money. However, the biggest disadvantage is; its value is constantly changing. You must calculate the amount you use according to at least 3% variability. Otherwise, you may lose a little while trying to make a profit.
While I agree that the volatility can be a pain when you gamble as you could have earned a lot of bitcoin during a session only to find out that you lost in terms of fiat when the market crashed, this is something in which we had years to learn how to handle.
Personally when that happens I think about it in the same way I think about my bitcoin investment, maybe its fiat value is down but in the future it will go up, besides we are gambling with satoshis and not with fiat so as long as I got more bitcoin in my wallet I think of it as a win.