Many companies make a profit center out of their shipping department, adding fees.
UPS fees are dependent on weight and volume of the package. They offer discounts to companies that use their service, so what ever the company charges over their cost is profit.
My son had a company making steel shooting targets, steel is heavy, and our freight bills were quite high, however we only charged whatever we were charged by UPS. This kept the delivered cost at a minimum for the customer. Every year, UPS sends out a new price list, and it was always a few % higher. That really multiplies after a few years of increases.
Also, the UPS "stores" charge 10 to 15% more than the UPS "list" prices, so if you can go to an actual UPS terminal, your shipping costs are lower than at the UPS "store"
I review the shipping costs whenever I buy online, and I hate it when people like Midway say they are shipping UPS, but they use the USPS as a final delivery service. It adds a couple days to my delivery.