I would say to be more carefull with the shops that advertise the lowest prices.
You can get to the bottom of what they say with a few questions. If they say it needs rotors or drums ask why. If they say it's too thin to machine have them show you the micromiter readings and machine to spec. You could subtract .020 from a disk or add .010 to a drum for machining. It could be more if real warped.
If it has bad groves in it it is probibly junk. Another thing that happens a lot is the breaking service chips off from rust under the breaking serface. Pobibly junk then. More often on orignal break parts. Been told one reason for this is because manufactures use recycled scrap metal for some things like brake parts and oil pans (some of those rust out too).
For frozen calipers ask them to show you. With a big screw driver the piston should slide back in. On ABS it's a good idea to open the bleader so the old fluid in the caliper is not pushed back into the ABS controls. It is also posable for the ABS to keep the fluid from flowing back into the caliper.
If the piston moves but the caliper does not slide then it needs the slides cleaned and lubed. That should be part of a good break job but is skiped by the hacks. There is also a hardware kit it could use if it does not slide.
The guys doing oil changes, tires, and oil changes all day don't tend to be the best of the bunch. A Chevy tec told me the other day on some of their newer ones it takes 5 different computers in the car and a whole list of sencers before it will allow the car to start. And yes they are paid to chaing parts at the dealer. Most of the time the manufacture does not pay dignostic time. Reasons like that push good guys out of the trade. Is that the tecs fault?