So the lack of caring (which takes up resources btw) defines Amex's intent?
And if Walmart doesn't change their return policy after all these years, that means they don't care about intentional returns? It's probably also impossible for Amex to tell you exactly how many cards is too many, so maybe that's why they don't make such rules.
You're being beyond krum.
If AMEX didn't like people maxing out SBS they could still have the same success with SBS with just primary cards. That would take exactly zero resources.
5 years later and they still don't care.
Why?
Because they have an SBS budget and sponsors for that budget. The more cards the merrier up to the limit of that budget. That makes it a success and makes businesses need to take AMEX if they want in on the fun.
AMEX isn't some company run by your friend. They know exactly what they're doing.
WM would have to throw the baby out with the bathwater to stop allowing returns. There's no way to effectively divine someone's intention other than banning repeat offenders (which does happen in many stores).