We don’t even have gates. Most people just pay for their tickets. Sometimes there are ticket inspections - if you get caught you’ll be fined. Way cheaper than enormous infrastructure for every entrance that just slows you down if you have an annual ticket for example. https://youtu.be/kq-X25pH1XQ
I don’t think that’s how it works. If it exactly looks like something protected by laws like copyright or whatever your country uses, I highly doubt that any court would say that it’s fine just because it was created by AI.