This is honestly one of the greatest uses of religious exemptions. It's not like the store is really making that much from every individual cashier they ask to hawk credit cards. But if they did make an issue of it, and you did sue them for violating your religious rights, then they would have to pay legal fees. And even a simple legal case would likely cost them more in legal fees than they would make from many years of you hawking credit cards.

You would get more pushback if you were requesting something that required serious accommodations on the part of the company. But simply letting you not sell credit cards? That's an easy one to get approved.