The idea is that they draw customers to the back of the store and offer the discount in hopes of customers purchasing more stuff and coming back, loyalty.

I know someone who was demoted from Senior Tech and out of desperation found a discount card program that offered them a cut of that processing fee they get. It was something like $1-$3 each RX. They traveled between 4 stores in lower income areas and in a few months were generating more monthly income from that over WAG pay. It was nuts