God, not this again.
Look, dude, Jim's arguments may be flawed or repetitive, but here's the thing:
Libraries.
I could end the whole argument there, but let me remind you of something: Game stores make most of their profits on resale. Back in the day, they made maybe 20 bucks on the sale of an Xbox. The 360 is unlikely to yield much more, particularly now that it's getting on a bit and is therefore cheaper (but only for you - it still costs the same amount to make).
So, shut down used games sales and you basically shot down the outlets that sell games.
I may be a fan of Steam, but I like to be able to install a game without waiting for hours while it downloads. Also, if you shut down game stores, Origin will grow - at least Gamestop doesn't pre-install spyware.
Also, the buck does not stop at Gamestop. If I buy a game (used or not) and show it to my friends, they sometimes get interested. If I don't already have a cracked ISO on my hard disk, chances are much higher that they'll buy it too.
This is called word-of-mouth, and the entire book industry is held up by it (see again: libraries).
Ever heard of the Baen Free Library? Baen distributes a CD of a huge chunk of their works in every book they sell (they're also available online now). Why? Because chances are if you like their older stuff, you'll just go to the library (you get the point). But when the new one comes out, if you're hooked, you're much more likely to buy it off the shelf. It's not a guarantee, sure, but customers are selfish arseholes by nature and we have every right to be (just so long as we're not rude to the people behind the counter).
I'm not sure at what point lending games effectively became illegal, but you try that shit with books, DVDs, music or any other media and watch the fireworks.