I can understand your fustration with pricing, and I can assure that what the dealer is charging is in line with what it would cost to get your vehicle worked on at the dealer, as well as what it would cost to have it towed in. Now don't totally blame parts cost on the dealer. They have some say in what they charge, but keep in mind the mother OEM is setting the MSRP and then the dealer discount is based off of that price structure. So OEM company can suggest a $50 MSRP but then will tell the dealer this is what you are going to pay us for the part. So a $50 part could cost the dealer $35-45 based on the discount codes.
And if you would study what goes into the labor rate I think you will find that it isn't as profitable as it sounds on the surface. A $25/hour employee with vacation, workmans comp, health insurance, taxes paid by the employer, utilities, and buildng upkeep can turn that $25/hour into $75/hour very quickly.