But ps3's system was meant for sharing with family. There was no other intent. We are sharing with randomn people, yes exploiting it, but it offers an unontrusive and easy way of sharing with our family/friends.
That was the original intent, sharing games with family in the same household, which was a very cool idea incidentally. But exploitation of it has limited that feature now for those that did want to use it that way which is a shame. But it's for reasons like this why Steam does what it does, they know people will try to abuse the system so they start smaller so as to not piss off their partners, and go from there. I mean take your app store game for example that you made. Let's say a dude bought it and liked it, told his 5 friends about it and they all bought it as well as a result. But instead what if that original dude that bought it instead just "shared" it with his 5 friends and his five friends as a result never paid for it, are you cool with that? If you told other developer friends that people were mass sharing your game rather than buying it, would they be cool with that and consider developing apps for the same service or would they go elsewhere? There's a line Valve (and others) have to walk so as not to piss off the development community on which they so depend. We're in this situation now where yeah drm and some of it's limits suck, but anytime they try loosening that people exploit it en mass and ruin it for everyone else. One day someone will figure out an acceptable middle ground but we're gonna have to crawl there at a glacial pace. So is Steams new family sharing ideal? Definitely not, but at least it's a step in the right direction.