If you purchased the speakers at retail from a dealer, I would expect the dealer to take care of the return for you. Otherwise, I think it is reasonable to expect to pay return freight. What if you think it's warranty, but an examination by the manufacturer finds you overdrove the speaker motor and it is fried? If they have a free return freight policy they have already lost money on something that is not their fault.
Most speaker repairs can be completed in the field except maybe electrostats and planars. So, maybe just buy speakers from a local dealer and/or stay with conventional driver speakers.