Casino will gets the biggest advantage than the gamblers because the casino have the business and serves the gamblers with many gambling games.
The casino is having a house edge, that matters. In the long run the house edge's effect becomes more prominent and the total loss of the players is more than the total loss of the casino, eventually making the casino profit more and thus have a positive net output. Hence the casino business is productive in the long run and it is why people like Trump have ownerships in casinos.
Be a part of the casino if you want long term profits, being a player will only bring losses if you dont know when you need to stop gambling.