The game is probably rigged--crooked, fixed. Tony and his guys can't lose. That's why they split up the winnings. Silvio's in the game to provide some "excitement" for the suckers--"gee, I'm playing cards with a real Mafia guy, woweeee!" The main objective is to take the money from rich suckers, such as doctors and businessmen, who keep a lot of cash on hand because they never report it to the tax people. They also get rich by advancing loans to suckers at outlandinsh interest rates. Tony and his crew don't aim to get people like Davey, who aren't real executives. But if they do, they bust 'em out: a sucker is a sucker.