Except that nobody owns games or movies anymore. I suspect that letting someone log on to my Steam account would potentially be grounds for a banning, and losing whatever investment I have in the platform.
Gamestop & friends seem to be muddling along through inertia, the larger-than-it-was but still-small retro gaming market (less Gamestop, they don't carry stuff that old), and selling non-game materials. And new games that come with DLC tickets and such. Not so much used sales or rentals (remember renting games from Blockbuster?)