The gamble that are played in such a place are gamble's that are illegal meaning the government is not in support of those kind of gamble and it could be because of the things the gambling may make you do or how bad it is, in my country gambling is lawful meaning such a thing is not there, the only time you will see something like that is when criminals are looking for a place they can come without people seeing them they look for a place like this to gamble is not as if the kind of gambling they are doing is unlawful is because they are criminals and they want a hidden place to enjoy there self's and have fun, people build a hiding place like that for gambling in other for criminals to come without fear of people seeing them and they pay huge amount of money just to have fun, so the police always come for the criminals and not for everyone in that place, however it is always advisable to stay alway from places like this because this criminal's comes with gun to that gambling place and sometimes they will want to resist arrest when the police comes there and before you know they will start shooting, someone has dead like that before so avoid such a place if you are not a criminal.