THis is not to defend these guys but......
SHIPPING is not just the cost of transporting the part to your home. It is also for the labor to wrap the part in a box, the box itself and the labor to load the truck that will deliver the part.
Do you work for free? I don't. It a good economy, wages usually go up to attract employees for the increased workload.
I do agree that in many cases, these companies charge stupid rates for shipping. It is like a New Car Dealer selling you on their paint protection plan....
I once bought some parts for a truck I had years ago. They didn't fit so I decided to send them back. When I went to the UPS box store, the cost to ship them back was about half of what the company charged me. I asked the clerk why....He told me that shipping is just another profit generating move that these businesses do.
I've bought full length fuel lines that weigh less than 4 lbs but because of the HUGE box that it comes in, the shipping was almost as much as the part.