I don't think I've ever been in a Wolf. I may go today as there's one downstairs from my client office, just because I am bored....
but I think as a generalization, because people know Canon and Nikon because of their branding and visibility in the market, it's easier to sell. And it sounds like a lot of these sales folks aren't much better than the sales staff at a Best Buy type store-that is, more often than not, you get regurgitated stuff, not their own thoughts or experience.
I buy a lot from Adorama, but I was sold on Pentax camera by this forum and my local shop in NYC. They carry all the big brands, (not too much sony, as the sales guys even tell the customers they only carry good cameras. woman didn't pick up on that one too fast...). I was at the time debating k100, k10 or a canon or nikon. admittedly, I was leaning heavily toward pentax to begin with, but even though they probably would get more from C or N sales than Pentax, the salesguy didn't push them. Basically knew I had done my homework, supported the theses I had come to, and that was it. He also said he shoots a k10d, but i think he may have just said that (or, he shoots em all because he's a good sales guy and he should know what he's selling).
Also, a nice thing to do, if you have a smartphone or something (or if the store had a magazine section....)...show them the k20d ad, either via the web or in print. that'll make em a little embarassed