Because people/companies that drive trucks for a living are forced to pay prices like this to keep the vehicles on the road. I bought these parts from Cummins today for a customer's fuel pump we are overhauling. This is a small spring, and an aluminum plug for a pump housing similar to a frost plug. Of course, I also have to mark these up even more when I put them on the job. This is straight up gouging, they aren't even trying to hide it anymore.