BTC gambling is already moderately popular. One of the most popular BTC gambling sites was
Satoshi Dice, which at some points took up absolutely massive amounts of transactions and was even considered an attack on the blockchain.
Due to the higher confirmation times though (or higher transaction fees, basically your choice) recently, it's become harder to gamble with small amounts of satoshi, which was one of the main benefits of BTC casinos.
There's also the fact that a lot of BTC gambling sites have started banning US customers and many of them are running shady businesses which have a questionable legal status. Anonymity is tough because governments will typically require age verification.
So basically, it's a good idea but it hasn't worked out too well in practice yet. Ideally some "ordinary" online casinos would start accepting it.