Plenty of companies already do things like this. For some products and some time periods businesses will over store credit vs. money. Private companies write refund polices and when you buy from them you are agreeing to the terms. If people stop patronizing them due to this the company is incentivized to adjust their policy. If consumers abuse a refund policy the seller is incentivized to change their police again.

If companies do not follow their legal refund polices customers will sue them or expose this to the public. This happens from time to time and usually is settled privately through arbitration (private law). If a company abuses their customers these days they will get lit up online and suffer very quickly. We've seen this many times.

Its honestly funny to me when people think we have to have the state regulating everything as it does. Freedom is much better, much faster, and much more profitable to all parties.