Ill speak up on this whole parts counter thing.
I worked for a chain auto parts store for 2 days. 2 days! When I started, they wanted to pay me 6.15 an hour (this was 5 years ago). So when I started out, they didnt show me how to do anything. Now, I know what the parts are, just not how the computer system worked, how the backroom was stocked, or things like that. Well, they basically left me to fend for myself and figure it all out. By the second day of customers being impatient with me, I walked out. The training is just that poor sometimes.
On the subject of girls behind the counters, sure there are some airheads that are there to attract business. But, I can tell you firsthand, I know a few that really know their stuff. I girl I used to go with does most of the work on her car, including changing timing belt, water pump, fuel pump, tune up, etc. She actually got a managers position at a chain store before everyone else that had been there for awhile already. The guys there dont like her very much because she can put them all to shame when it comes to cars.