I find that when I go into my local Best Buy, either (a) they don't know what constitutes browsing behavior, or (b) they just don't actually want to help you, but want to provide the impression that they do. If I'm just browsing, it seems like every other minute, I have one of their people walking up and asking me if I need any assistance. But then, if I actually do have a question, I can't seem to find anyone or get anyone's attention. I'd say maybe my "just browsing" behavior is different than most people's, but I'm not the only one who I've seen mention this, so I'm pretty sure I'm not alone on this.
Though of course, if I actually want knowledgable staff, I go to the local place that I bought my Sony XBR8 from a few years ago. Their brand selection isn't as wide, but they are a locally-owned, non-chain business, and they know their stuff (and have higher-end selection). A few years ago, the experience of just wanting a short (6 foot) cable to hook up my sub, and being told by a Best Buy goon that "a digital coaxial audio cable won't work for a sub because it doesn't carry the frequencies the same", that really made me acutely aware of just how little they know (like that wire is wire is wire).