The value of the price of the part is tied to the need for the machine. I was once called into the office at work and a woman accountant sat smuggly as the Plant manager asked started to grill me for paying $140 express shipping for a $3 plastic gear that came in a padded envelope from Germany. I explained that part has a press down that is costing us $600/shift. The plant manager replied he agreed with my decision, and looked at the woman accountant who was murdering me with her eyes. If I need the machine, I need the part. The part/shipping price is a secondary concern. Shipping costs money, shipping boxes and clerks cost money. Someone has to pay it.
Shipping is irrelevant. People will go to Starbucks and pay $6.00 for coffee or to a bar and pay $10.00 for a mixed drink. Sit at home order parts, do nothing except wait a couple days and it is on your doorstep. Would it have been cheaper to drive to the store? If so, fill your car with gas, stop at starbucks grab a cup of coffee, drive a few hundred miles stop for a beer and a sandwich on the way home and it would have cost you plenty more. You agreed to the shipping, if you don't want to pay it then don't order it. It is all about convenience which is worth way more than a few dollars.