The casino has built in advantages everywhere in the house. At the Poker Table they take a small percentage of each pot, that means who ever winso or loses, the house skims the pots both ways. So the poker tables will make money as long as there are players sitting there to play.
The slots are set to return at least 2% of every dollar dropped into them. This is above and beyond any jackpots paid out, so the slots always make money for the house two cents on every dollar and who wins what is immaterial.
The Roulette wheel in an American Casino pays out set odds on every kind of bet, and there are lots of bets to make. There are thirty-six numbers, Zero and Double Zero, yet if you bet a single number and win your odds are 36-1, not 38-1--again a built in percentage for the house. This translates across betting number blocks, odd and even, red and black, and the three "Dozens" on the wheel. Zero and Double Zero are not odd, they're not even and they're not part of the dozens, and they are GREEN, not red or black.
Again the money coming into the house is guaranteed every time a ball hits the green.
Black jack is the best odds for the player in the house, that and the crap table, but they are still weighted to the house from the get -go.
In other words the house NEVER needs to cheat. At least not in legal gambling houses.
They rake in 2-4 cents on every dollar that gets wagered, whether it's a pay out or the player loses.
And in legal gambling venues this is all guaranteed as honest as the guidelines on how the casino is allowed to make money. If One million dollars crosses the table on a given day, that's $20-40,000 dollars for the house. And, yes, millions cross the tables each day and the casinos turn that into investments, loans, real estate deals and turn further profits on each endeavor.
They do not need to cheat.
Now non-legal gambling is a total crapshoot. It is often dishonest and of course, it is unregulated.
Regards,
Scott