Actually, my close friends and cousins have my account stored on their PS3 so when I get a game they all get it too. Ya it isn't 'lendable', and I can't carry it around since it isn't a physical copy, but it is share-able, at least on PSN. And I have PS+ too, so we've gotten quite a bit of downloadable games to play together over the time.
The only advantage digital downloads give for gamers is making life a bit easier for lazy people, you can no longer lend your game to friends/family & you certainly can't sell it if you want to. Physical games/media will always be superior, digital only benefits the creators.