BRAKE MASTERS slipshod job TUCSON, Arizona

my car stopped on the road and I took it to Brake master on oracle road. they checked my car 15-20 minutes and told me that I need to change fuel pump.I did not hove much time i had to leave. next day I changed it in another service considering what Brake master said was correct. but my car stopped other day.I took it to a guy who is friend of my friend.he told me that problem is about fuel sensor.he also told me that when they check the car computer says problem is on fuel pump but when once you check fuel pump you dont see any problem.Now I wanna ask to Brake master:
YOU ARE PROFESSIONALS.YOU ARE SUPPOSED TO CHECK EVERYTHING DEEPLY, THINKING THAT THERE MIGHT BE ANY OTHER REASON BEHIND IT.WHY DID NOT YOU DO THIS?YOU JUST CHECKED MY CAR 20 MINUTES AND TOLD ME THE ALLEGED PROBLEM.NOW, IS THIS THE WAY YOU USUALLY WORK? WHY ARE YOU SO EAGER TO FINISH YOUR JOB A WITH CUSTOMER AND TO CHARGE HIM A LOT MONEY?