defective covers for s5

I bought a body glove for my S5 for R199 on the 20th of March, by the next day it was cracked and damaged. I did not drop it or damage it myself. when i went back to the store for a refund i was told the supplier will not exchange the cover because it was fine when i left the store. all other shops i know of accept their damaged or defective goods if it was not the customers fault. shocking, cell c.