But employees do not equal the company. Unless the gamestop headquarters released a memo to all stores "Convince customers to sell their copies of Killzone 2" then it's not gamestop purposely attempting to profit from ignorance. And if they did release a memo like that it was take all of ten seconds for it to explode onto the intarwebs. Just because they do profit from ignorance doesn't mean that they are purposefully taking advantage of ignorance.
Look at how Gamestop is run, and how they have things set up. It is all corporate driven with the employees being sorting drones for getting merchandise on shelves, and working the point of sales devices. The employees learn scripts they do, and follow a set procedure. And the system is set up to lock you in to keep money there. It is meant to capitalize on this situation and exploit it. It is also prone to doing dumb things, like the prelaunch and they still make monety off it.
As far as "employees do not equal the company", a company consists of employees and systems they work. If you see the same level of ignorance on the part of employees, that shows you what the company is.