Asking whether bitcoin casinos are legal is like asking whether is cannabis legal or not. Well, it depends on the specific laws of your country. If your country requires licences for them to run and to comply with anti-money laundering and know your customer laws and they don't then they're probably not technically legal or allowed to operate in that jurisdiction. I would check your own countries laws and what they require for an online gambling business to operate because nobody can give you a concrete answer without knowing where you reside.
the legal side of bitcoin gambling can be on your side. In certain situations bitcoin gambling sites are completely legitimate to operate and participate.
Yeah, it's clearly hilariousetc said that we could not build concrete answer if we don't know where you are residing at.
So, if in your place bitcoin is legal then yes you can operate gambling site and have licensed to operate.
Some countries not having a law regarding cryptocurrency so they are free to used bitcoin and casino site mostly they used digital money or bitcoin as betting money because it is convenience to used like paper money.