First off, those Dual woofers are 12's, not 15's. Best Buy doesn't offer anything other than 10's or 12's, bar none (except a year or two ago, when they experimented with some RF stuff that didn't sell, and a powered RF 8" tube that's horribly overpriced and doesn't sell).
For most of you guys, yes, most of what BB and CC sells isn't adequate. You want higher-end, nicer stuff, and are generally willing to pay for quality. For Jim Bob and Betty Sue customer, they just want a CD player for their Neon that plays CDs. Or speakers that don't sound like 2 monkeys humping. I've worked in car audio for a LONG time, including your high-end custom shops, as well as a CC at one time, and a BB now. All of my gear, with the exception of my wiring, came from elsewhere. Excelon, CDT, eD, Xtant, is what I run.
What I'm saying is, if you don't like these places, don't go there. I don't like women's perfume shops, but instead of *****ing on online forums about them, I DON'T GO THERE. These chains have 400-700 stores, and have to hire at least 10 people per store for car audio. Of course you're going to find some morons. And yes, they're going to try and sell you some $20 kits, $100 amp kits, and a warranty on everything. It's their jobs, and you knew it before you went in there. *****ing is useless, unless you have a solution in place that will solve the issue.