There is a rather obvious, though not necessarily correct, answer to the question of the books having less value (e.g., less Safeway value mentioned above) or poorer selection. Businesses use incentives such as coupons to attract new business or increase business. When the cost of the incentive outweighs the increased profit, businesses drop out.

Only a very limited type of business repeatedly uses coupons - car washes are a good example. These are businesses where the price with a coupon has become the actual price and no one will go without a coupon. But good restaurants don't need to do that. Or alternatively, their regular customers use the coupons and those discounts defeat the value of attracting new customers.

Incentives are a very tricky and complicated aspect of running a business. I do not have the real answers, but having worked in several businesses, I do know how complicated it can get deciding whether coupons are or are not worth the effort and the cost.