I don't allow this after I witnessed it myself.
After my oil change the tech takes the car for a 5+ minute test drive. WTF? I was in today and made them write "NO WASH-NO TEST DRIVE" on the service order. I doubt they take my wifes Outback for a test drive after an oil change.
I like having the dealership do the small things while I've got a warranty. Their fast and friendly here in Auburn,WA. Plus my car is too low for me to change it without ramps which I haven't purchased.