Shocking service

Shocking service. I purchased a 12kg bag of Hills biscuits, price R 1800 odd from Boskruin Vet. When I attempted to open the bag, the inner casing stuck to the outer packaging and the result was that the bag tore at the top, which means the biscuits will go stale. I returned it to Boskruin vet, wanting a new bag, (I purchased it 2 days ago.) After standing arround, waiting to be served for 25 minutes, Markus refused to take the bag back.. I'll never buy food from them again. This isn't the first issue I've had with them. Either the bag doesn't have a zipper, or, the bag pop's open where it's supposed to zip closed, and now this. This is expensive food. Who in their right mind, would purchase food, deliberately destroy the top of the bag, stand around for 25 minutes waiting to be served, ridicules, but that's what they seem to think I did. Disgusting. And Markus' attitude, couldn't give a damn. Shrugged his shoulders at me.