I can understand, and to a greater or lesser extent agree with, your feelings regarding garage charges Toshi---I helped set-up and was then the senior Service Excecutive (posh word for a service receptionist, but we did a lot more) at a M/Benz garage. The manufacturers set strict 'job-times' and with modern cars, service work is diminishing at an alarming rate (for the garage), yet the customer still wants your technicians to be fully trained and conversant with all the models---and the courses are NOT free, the garages have to pay for them , and any accommodation if it is more than a 1 day course.
I once had a customer come in (about late-afternoon) with a broken headlamp glass. He wasn't local, and it was imperative that the glass was replaced so that he could drive home (in the dark). I squeezed his job into the workload, and the technician bust a gut to get it done (so that the job I took him off still went out that night). I charged him the M/Benz book time (about 0.7hrs--you had to recheck h/light alignment as well), and yes the technician HAD done it in less than par time. Despite the fact that we had really dug deep to rescue him, he made such a fuss over the charge, and was so 'publicly' rude to me and about the garage that the Service Manager had to reduce the charge--and I later got a bollocking from the Service manager for charging the book time! I was not a happy bunny! Also, don't forget, in these large franchise garages, the manufacturer has a lot of control over the running and layout of it--it not always the garages fault. To retain the franchise they have to hit targets and jump through a lot of hoops. Lastly, the only way the technician can earn any bonus is by doing his work in under par time, and despite what people think, the garage business is not a well paid trade, and with all the electronics now in cars, there are (and have to be) some very clever people working to keep you mobile.
I have spent the bulk of my working life in the motor trade, with about 20 of my final years on 'the front desk'