Well, you really dodged a bullet, there.
They could have said, "these cables are not in their original condition", and said you are stuck with them.
Or they could have said, "you damaged them yourself, so it's not our fault".
Or, they could have said, "well, these were defective, and they have an "exchange only" policy, which says they don't have to give you a refund or even store credit. we only have to give you a replacement of the same crappy cables".
Always go with heavier cables - more power will get to the dead battery, and the extra cable size will not cause any problems. Bigger is better for cables!
And always remember to steer clear of Crappy Tire and their crappy policies - next time, you might not be so lucky.