Matrix is a thing. We use one at 15% over MSRP per the owner. Not a fan personally, but when the guy who signs my paychecks says to do something, I do what he says. I usually only use it on those "mechanics" that never tell me who they are when they call and get offended when I ask.
FWIW I give 20-25% off MSRP on wholesale even to collision. We make substantially more money selling parts under Ford warranty now, cost +90.89%, that we literally lose money dealing with wholesale and all that is involved with it, compared to billing out warranty parts where there is no questioning or arguement. What shops do when they bill out their parts is up to them, I don't judge or care.