> yes they can set up weird rules for their shop, but it's dishonest to change the game now, and frankly counter productive

You agree to their terms before entering the shop. Everyone understands and knows this. Pretending you don't know their terms is willful ignorance. The moral issues here have been settled in law for centuries now. The only thing that actually changed is technical capability.

A much better analogy is this: You walk into a music store, and there is a sign that says "Please do not play the instruments". The shop owner walks out of the store, and you start playing the guitars because "they're not here to enforce it, so the rule doesn't apply".