It's been years now since I checked, but I remember needing (within hours) a specific ethernet card (for a box running Solaris x86 -- back in the late '90s/early noughties driver support for Solaris was quite limited) and went to a BestBuy store as they had it in stock near me.
I checked later on and found that the price in the store was 30% over MSRP.
As such, the fact that the price was the same at an airport vending machine vis-a-vis an actual store doesn't surprise me that much.
Which is why, unless I'm in a situation like I described above, I stay far, far away from BestBuy.
Obviously, this is anecdotal, so I imagine YMMV.
While I get your point, that I'd even have to compare prices online and in person from the same retailer, even if they will "price match" (which is really just ripping off anyone who wouldn't think to look for a better price from them online) is slimy as hell IMHO.