Vaio Ibm

In most electronic stores like Best Buy, Circuit City etc…?
why do all of them have only a few laptop brands that they are wishing to sell? For instance, like Sony Vaio, Gateway and HP Pavilion. I agree that these laptops are very good – but shouldn’t they also sell some other laptop brands like Acer, Fujitsu, Alienware, Lenovo/IBM etc. which have good models to suit user’s needs?
It’s ok if Best Buy has only Sony, Gateway or Toshiba. But why does even Frys and Circuit City also have only Sony or Toshiba?
Why can’t each store sell different brands and wider range of laptop models? Why do all stores only sell the same two or three very popular brands of laptops?
Those stores get paid by the certain companies to put there certain brands of there laptops on the shelves.
Huge Laptop Collection (Updated)