Like any other legal or regulatory matter, it depends on the situation and the legal affairs of it. In the USA the position of most state regulatory agencies are extremely strict and accountability usually prevails.
As far as pre-shuffled cards, there are various methods that do exist, and used by different casino properties. One is the auto shuffler and two, the pre-shuffled and sealed shoe of cards performed by a state certified company that preps such and ships the shoe to the casinos, they are numbered and sealed and opened at the table and then cut.
As I said, different casinos have different protocols. Many will do a quick shuffle, a mini shuffle of a pre-shuffled shoe as well. More so within the high limit rooms rather than the main floor.
My daughter was the chief compliance officer for the largest casino in the southeast part of the USA for well over 10 years and she was the liaison and compliance officer with their state regulatory agency and I do know that she repeatedly said the compliance by the casino was spot on, past exemplification and without any challenge whatsoever on behalf of the casino.
Are there doctors or attorneys that willingly violate their state ethics and criminal statues for the furtherance of their monetary gain? Sure, every once in awhile there are handcuffs thrown on a doctor or an attorney and they are convicted and imprisoned as well. Is it the bulk of them? Is it more than a few here and there? I don't have the statistics on that, you answer that one. Are there restaurants where the chef does not wear gloves and picks his nose with that very same gooey substance just happening to fall into your Beef Stew?? Does your local new-car dealership certified factory service actually cross every single 'T' and dot every single 'I' with the proper technical procedure for the brake job they just performed on your pregnant wife's SUV? The list is endless.
Is there wrong doing within the casino? Is it wide spread? Does it effect everyone? How can that be absolutely answered with certainty to everyone's satisfaction?