Banks look like idiots agreeing to give up margin and signing onto this but once one agree's they all have to follow suit or risk losing customers.

Correct me if I am wrong but couldn't a consumer add multiple cards to their Apple Pay? As long as the bank brand can be added what reason do they have to actively promote Apple Pay? Detracts from their margin if consumers still prefer physical card use so if I was them maybe I would sign up but I sure wouldn't actively promote it like they are and I would probably try to build my own mobile service where margins remain high.