hedwards: [1]How many people are going to do that though?
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[2] Also, keep in mind that since they have to buy the game in order to return it, the company either gets a low interest loan for that period of time, or they know the money is theirs, and can offer store credit depending upon jurisdiction.
lumengloriosum: [1] I can't argue percentages, but possibly close to piracy numbers. If a person can pirate it for the sake of just wanting to play a game without paying, I can't see why they wouldn't just abuse the system either. It's not going to be large scale like 50% of the audience. Your examples I would have to argue are irrelevant due to the nature of software being a non-physical medium. Sure some stores get the product back used/abused, but that is a physical material that they can still salvage further down the chain in a discount section or something of the sort. It's not a total loss.
Software on the other hand is license only, refund only, no resale or down the line discount or such. The problem would be relieved by physical mediums, but at the moment there is no way to ensure Digital only cannot be abused by such laws if refunds had legal backing.
[2] The problem is more in relation to the developer/publisher and the store front. Sure Steam can offer store credit for the refunding, it's still going to eat up revenue somewhere which the Storefront must compensate in losses. Combined with a legal lawful backing, economic issues that people use to justify piracy and don't care for keeping a particular game... There's nothing to prevent abusing the system theoretically. Low interest loan would be possible, or possibly a "refund tax" which simply compensates for a 'potential' loss in refunds.
Think about D.R.M. Who funds the anti-piracy measures that pirates keep breaking? You, the payer in the price tag.
I doubt that very much. If you're going to do that, then you're going to pirate the game. Why give Steam the money for that period of time, if you're just going to use it as a means of pirating the materials?
As far as your second point goes, I doubt that, the vast majority of the bad actors are probably going to continue to pirate software. You might have a few that do this for online features, but really, how good are you going to get at an online game in only 2 weeks?
hedwards: How many people are going to do that though? Return fraud is a thing in the US and yet many companies opt to have extremely liberal return policies. The "local" outdoor gear coop REI used to have a policy of accepting returns no matter how long ago the item was purchased. They did eventually have to end the policy as people would go around to yard sales and buy up old gear for return. Now, it's limited to 1 year, I think.
Similarly the local warehouse store Costco will take things back with very little questioning, this has led to crazy things like dead cut christmas trees being returned for a refund.
Sometimes, the policies do need to be revised, but often times the extra sales you make to customers that are on the fence makes up for the return fraud.
Also, keep in mind that since they have to buy the game in order to return it, the company either gets a low interest loan for that period of time, or they know the money is theirs, and can offer store credit depending upon jurisdiction.
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Pheace: One issue with this I imagine, for online purchases at least, is if the 2 week/2 hour thing on Steam could be used as an 'endless' demo without recourse it would become a hell with the payment services and reverting/undoing payments all the time. I don't think any fees are involved there but I imagine it could quickly become quite hell of an administrative mess with the volumes Steam can reach to. It's not as easy as just handing money over the counter.
As I said in the post that I hadn't yet posted, why bother? If you're going to do endless demos, then you might as well pirate the software and be done with it. This might somewhat increase the cost of doing business, but probably not by as much as people imagine. The worst abusers are likely just going to pirate anyways as it's a lot less effort than paying for a game and then seeking a refund while trying not to miss out on the window.
A lot of hassle to get a game without paying. At that point, you'd be better off just pirating the game rather than engaging in return fraud.