Re: Quality standards of service work:
Level of quality with service provided must be maintained so wheels don't go out of true or adjustments of brakes and other components after it leaves the shop int he first place. It's basic bike shop customer service. If there are boomerang repairs, I think an investment in training of mechanics and service writers needs to happen before service time is given away. And I'd be really surprised that other local non-coop bike shops would allow a climate of boomerang repairs to be present. It's good business to make sure that happens, no matter how the shop is structured or modeled.
Co-ops, DIY skillshare, and non-profit shops really can't afford low service quality levels. In Portland, the Co-ops and non profit street level shops often do a HIGHER quality repair and tune up than the bro-shops filled with SRAM Red and Dura Ace. Unfamiliarity of high end components is an entirely different issue i my mind; there's a lot of expertise to execute on cotter pin boom bikes and old Schwinns. The people with those bikes will pay for good work done; they will be more pissed off when they pay any amount of money on a crappy repair that doesn't address their problem, or makes it worse.