I am not sure that answers my question. My question was if the house knowing what the cards were would actually help the house at all.
Assuming it doesn’t then why would they KNOWINGLY use “marked” cards, as some people have suggested.
The law posted above said KNOWINGLY use. If they didn’t know, and it doesn’t appear that they did, for various reasons listed above, then they aren’t afoul of that law. Heck I wonder if they could sue the card maker for selling cards that are supposed to be identical on the backs.