Steam Store Refunds

If you know what I mean.

This. It's not the best of the ways, but I downloaded Skyrim from ThePirateBay to test it out before buying it on Steam.

(And I did bought it after playing it a bit, as you can see in my Steam library.)

+1 This. Someone might not agree, but it's the best way. And not really harmful for the developer, unless you consider selling a bugged mess that crashes a lot a fair business.

I don't think you can compare digital products with physical ones because all the physical products you can get a refund on have more than 24hours of "gameplay".

No, you do not (neccesarily) have that option. That stores in most cases allow you to, is a different story, and is to keep customers happy. Or in other words, stores don't have to accept a return. Unless of course they state that themselves in their polices.

But there is no law which tells stores that you may return something to a store if it is not to your liking. In fact, the idea of not being able to check a product thoroughly before purchasing, is the sole reason that stores have to accept it if you return an item when ordering it for example online, instead of buying it in a physical store.

Games are a though subject here though, because you can pretty much get as much information about the game in a physical store as you can in a digital store.

A defective product is something different of course, we are talking about a product not being what you expected here.