High Risk of annoying "interest group" complaints. There's a lot of evidence about how much just a couple of loony religious groups send thousands of complaints each year to Visa/Mastercard/etc about every company they don't like, and that in turn affects Visa/Mastercard/et al's pressure/relationship with banks.

You'd think that annoying complaints from a minority of self-righteous people wouldn't have so much power in banking, but they seem to get listened to time and again.