I worked as a Mechanic during this time frame. I have never seen rates and charges that low. The poor guy can barely print.
We used to run a $9.95 oil change special to get the customer car on the lift. Then we would tell him all about what was wrong. Crunching rusty tail pipes with pliers, pointing oil leaky shocks and torn ball joint boots, noisy wheel bearing, sloppy U joints ETC.
That went along with compulsory underhood and tire service for gasoline customers at the full service pumps. We didn't rip people off - that is bad for business- but we made our money. This was all helped by ARCO only charging us $770/mo for leasing a 2-1/2 Bay service station. A few years later corporate cranked that up to $1400/mo and drove us out of that spot. The Shell went in with the convenience store model. Bye, Bye Full Service Station.