It's the angle they're taken at. The piece above the glovebox comes off fairly easily, and if we could find a way to get ahold of them the US market could easily self install those bins, but the problem of things shifting, and flying out will still be there.
It takes no room from the glovebox that hasn't already been stolen by a blank plate that serves no purpose and that's why I'm sure some people want it just to have a little more room.