When my girlfriend and I went to go get her Toyota Prius' oil changed, the guys said we needed a new air filter. I told them "no thanks, the filter was only a month old...." Then they wanted to check all the fluids and the battery. The only problem with that is that the Prius battery is in the trunk, and since it is a highbrid, when they opened the hood, they didn't really know how to react. You can't get to most of the engine components because of how specialized the car is. So they finally grinned, realized they didn't know how to deal with this car, and just changed the oil without any other fussin'.
O, and when we took my girlfriend's minivan into a different place, the guy tried to get us to have him do the ****** fluid because it had metal particles in the fluid.... Well, the metal particles were in his very dirty hand as he wiped the ****** oil into it. I just happened to catch him doing that. So watch out for that trick.
This is why I change my KJ's oil and everything else.