It's not great, but it's not really "unfair". That is QVC's rule.
You can pay for shipping on your own, instead of using their prepaid label.
Box them up. Take them to USPS, UPS, FedEx, however you like to ship (I use paypal. Weigh my package & pay for it on paypal. Print out a shipping label & send it back.).
It is still expensive to ship back anything with some weight to it, like 4 shirts, but cheaper than $27.80.