Actually, last I heard, the positions at Radioshack are retail sales positions - just because you can build a TV/cell-phone/dvd-player doesn't mean you can sell one! Not to mention salesmen/women with _too_much_ knowledge probably just confuse the customers! (I'm sure this is why they want to check people out first, before handing them the keys to a store)
Maybe back in the day that was true, but I haven't been in a Radio Shack in the last 15 years where there was any clerk who knew a woofer from a diode.