I do not think you got ripped off at all. Your post is not the only one of it’s kind that has come across this forum. Lots of people, for whatever reason, will pay to have work done on their car, then start looking up the cost of the parts they had installed on the Internet, or call Autozone to have it quoted, then feel like they got ripped off because they could have gotten the part cheaper at Autozone or from a mail-order online source. It even happens sometimes in the repair industry, where a customer will come back to the shop angry because they went to autozone and found out they could have gotten the part cheaper than they were charged at the shop, and demand an explanation. Here’s the truth:
Every kind of business is in existence for two reasons: to provide a needed service and to make money. Like any other business, repair shop need revenue to pay their employees, utilities, insurance, and mortgage/rent. Sometimes equipment breaks and needs repaired. Scantools need to be updated periodically to work with the cars on the road. Alldata subscriptions need to be paid. Sometimes, a replacement part will fail before it’s time and the shop will have to eat the cost of the new part and the labor in order to keep the customer reasonably happy. All this can’t be covered by labor rates alone. Similar analogies can be made for other types of businesses as well. If you knew how much Walmart paid for that flat screen TV they’re selling for $900, it would probably make you sick…