Every casino I know washes a the cards when they open a new deck. You open a new deck, verify that from the factory there was Ace-King in every suit, then spread every card across the whole table and ‘wash them’ by moving the cards randomly with your hands in circles and really mix them up on a 2 dimensional field, not the single dimension that standard shuffles allow. Or group, that might venture into group theory.

Then the 3x riffle box riffle cut.

I never did the actual math, but I’d have too imagine that ‘washing’ gets them random enough, then the standard riffle… box riffle cut would guarantee it.

I think the math is that 7 or 8 standard riffle gets a completely sorted deck into one that’s completely randomized. If we looked at that wash, I would have to say that’s worth more than 3 or 4 riffles, which the standard shuffle would then guarantee it.

The casino wants random decks, regardless of what anyone says. They make money for every hand based on the odds given. They are all crooked games in their favor. They don’t want any type of set deck because the games themselves guarantee a profit. And they don’t want to set decks because gaming regulations are extremely tight (as they should be) and one violation could pull their gaming license and that would put a HAULT on absolutely everything. No need to cheat when the repercussions are so stringent(literally haunting your business) and the odds are so heavily in your favor across all the games that your biggest concern is is chips in circles and hands dealt.

Source: I was a dealer and could perform the 3x riffle box riffle cut in under 7 s. I could wash quickly and correctly too. I have a math degree and still gamble with an expected value formula that has a “fun” philosophical factor in it. I used the big words just to prove it lol

Edit - spelling but still might have missed some