question about 2003 27DS Greyhawk rear brakes

[ted h]

I had a recent rear brake job done on a 2003 27DS Greyhawk. I was told by the truck repair shop a reputable company that on the back brakes there are 2 brake pads used on each side only for the 2 wheels. This rig has 2 wheels on each side of axel and that actually these 2 wheels work by braking together with 1 set of brake pads. My first thought was that each wheel would need brake pads and that I should have received brake pads to all 4 wheels. I just wanted to see what you thought, I am new to RV world and trucks in general. What kind of mileage should I expect from new brake pads?
Thanks, TED

[Boss Wagon]

Each side , two tires, has one set of brakes. with two pads. The rear pads should last many miles.

[ted h]

Thanks roadrunner!