most large companies, maybe, but small-to-medium-sized businesses can and will tell you to take a hike. there are no consumer protections in the US regarding returns beyond the goodwill of the company
Perhaps because you don't want all retail to be Amazon?
> laws are not free, somebody has to pay
Isn't that a bit hyperbole? That law is written once, and delivers its effects afterwards. In contrast, millions of buyers have to investigate return policies every day without such a law. Is that really a better use of time?
And you don't have to buy on Amazon, most companies in the US accept returns in this way or another. Some ask you to pay a small premium for returns, it's up to you to pay it or not. Those who don't accept back damaged goods (no matter what policy is) usually got chargebacks which are commonly approved by the banks, and it's pretty expensive for sellers. So there are many ways to regulate returns, law is not the only one.
There's a lot of overlap between protecting consumers and enabling scammers.