My personal feelings on retailers is that if they stock the product and try to be helpful, I go with them. My problem with Apple products is that even the authorized dealers stock basically nothing.
I bought my last computer (easily the largest Mac purchase I ever made) from a store in Edmonton, from an eMail inquiry. I had first returned to the same store I had bought my G4/400 from, but left when I discovered not a single Mac on display. I also visited 3 other so-called Apple Resellers and found no product there either.
All London Drugs had to do to get my business is to be in my town and stock the product. They do, so they will get first chance at all my future business.
There's nothing inherently wrong with Future Shop, Best Buy, etc but they are no place for shopping. They are places for purchasing. A consumer who goes there for advice, after sales support, etc is setting themselves up for a bad experience, sooner or later.
If you can do your own research and are comfortable with your decisions, Future Shop and the like are fine. If you need any hand-holding at all, are relying on them for product recommendation or assessing of your needs, or aren't completely comfortable with the manufacturer's service or warranty, you are in the wrong building.
I once sold literally millions of dollars of retail electronics at my own business; I know more than enough to set my bull**** detector on "high".
Not stocking product because you want to pick and choose only the high margin/quick turnaround items generates no sypmpathy from me. If you are a dealer for a line, stock the damn product. It's an everything or nothing deal; if the whole line doesn't sit well with you then sell something else.