I did a quick search, just for fun. My local BestBuy has a Zotac GTX 470 for $380 (Canadian dollars, pretty much equal to US$ these days). With 13% sales tax, that's $429.
My favorite small local store that specializes in computer parts has the same card for $395. With tax, it's $446. My second favorite $382 ($432 with tax).
NCIX.com (Canadian online retailer) sells it for $380 + about $10 shipping, and with a $30 mail rebate. That is, you pay 380*1.13+10 (+0.5 for a stamp) and MAY receive back $30. (Multiply by 1.13 because there's a sales tax of 13% where I live and it applies to any online purchases I make from Canada.)
Total $440, or $410 if you're lucky and the rebate check arrives.
Newegg.ca: $361+$11.49 shipping, and there's a US$35 mail rebate. This definitely wins, but it's not by much IMO. If the rebate never shows up, it comes to $420. If it does, it's $385. And when you have a cheque denominated in US$ and you live in Canada, more headaches
Tigerdirect.ca (another online retailer) has it for $444. After tax, $502. No rebate. I didn't even bother to find out how much shipping is.
Of course, this is a statistical sample of 1 product, i.e. shouldn't be used for conclusions. Still it looks like BestBuy can be decently priced. You pay 10% more than at Newegg but you get the card right away, RMAs are not your problem, no paperwork to fill for rebates, no worries that the rebate won't show up. It's also cheaper than some online retailers and than some small local shops.
Sorry about the wall of text
Now, I'm not really defending BestBuy. I only buy stuff there during Boxing Week sales, when they do sometimes beat the online retailers by a nice margin. Their choices are extremely limited, so I don't like them much. Still, I don't get why some of you guys hate them so much.