Signing Customers Up For Rewards Without Their Consent. (alabama)

So I work for a retail office supply store, specifically in the Print & Marketing department. To make a long story short, our department doesn't get a lot of signups for our store's rewards program. To address this, both our new GM and corporate office wants us to take information that customers give us when they place orders and, if they don't already have a rewards account, sign them up without their knowledge/consent.

Personally, I think this practice is very scummy. While there's technically no downside to having a rewards account, signing them up behind their backs feels wrong. Especially considering we have a large percentage of customers who are elderly and don't even know how ther own cellphones work, as well as customers who don't speak a lot of English. Furthermore, we've been informed by said GM and Corporate Office that if we don't do this, we could potentially get fired.

My question is simple: is any of this legal? Does signing customers up for rewards behind their backs violate any laws? Can my job get away with firing me or anyone else for refusing to comply with this demand?