you'd have to do a hardware mod, and gaming is a regulated industry. so every mod you do has to be submitted to a state or nationwide gaming regulatory authority, takes months (at least) to get approval, and costs easily $100k.

Not to mention full regression testing on the statistics of the game. You would have to "re-prove" the validity of the RNG , which requires another QA cycle, statistical expert, and game designer (to ensure that the frequency and distribution of wins matches the specification sheet)