Wasn't the pre-Christmas expansion of Surface sales into non-MS stores a last minute thing (they were originally going to do it sometime in the new year)? If so, I'm not surprised Best Buy would put the display in some random less desirable place in the store. The best locations were probably already spoken for in advance of the Christmas shopping season.
Sure that's likely a factor, but again just highlights MS's incompetence with Surface overall. Advertise the hell out of it, make it only available online and a few MS stores that most of the population don't have convenient access to, then with a couple of weeks to go before xmas figure "Hey! Maybe we should make these available to more people!" and cram them into Best Buy. I can't fathom what they expected to happen with limiting Surface to MS stores and online even if it was reviewed highly, which it wasn't. It's just staggering to see MS seemingly living inside a titanium bubble lately.
Not that I think availability was actually the #1 problem, RT is just a seriously flawed product right now and the RT hardware was behind the times from the get-go. Even they were in more retail locations a month earlier I still believe the sales would not have had virtually any impact in the market.