My friend got an oil change done at kmart auto, except they forgot to refill the oil!
How on earth do you manage that!
The guys I've used at my local Kmart shop are good. They do a fair bit of stuff for me on the cheap (or for beer) and it's a small local workshop at a Shell servo in Umina. They get a bit busy at times but these guys know their shit and I don't mind using them for stuff I couldn't be bothered doing myself like pressing bearings. I think the larger ones in shopping center carparks should be avoided. They are busy as and mistakes are more likely to be made as you mentioned.
As for wheel alignments..... I think it has a lot to do with the mechanic who does it and their experience. Old school aligners know their shit.
Why people pay money to get their oil changed is beyond me. If you can put oil in a car then you are 1/3 of the way through an oil change. Such basic maintenance & it's saves you a shit load of cash in the long run.