I don't really know how this works

So P has a PS3 and plays the New Console Games that I turn up my nose at.

He can wander into the local shop and find a selection of great titles, used or new, marked down to £5 or £10. Big-name things that even I who doesn't USE a PS3 has heard of.

I can walk into the local shop and sigh that every DS game I have any interest in, even a used copy of a game that came out five years ago, is STILL over £20. How the heck does that work?

(Okay, some exceptions. Rhythm Heaven they have cheap because for some reason it's not that popular. I liked it, I already have it. Also Flower, Sun and Rain
because that game was too WEIRD to catch on. If I were desperate to buy something I might have gone for it.)

Really, I buy most of my DS games online, new, and still get a better deal.

... of course part of that is that they tend to cost less in the US, and now we come back around to why I refuse to buy a 3DS :) I do get some British-bought games, though, so just getting a US 3DS still wouldn't help.