Guinea Pig festival in Peru

I just saw the annual Guinea Pig Festival on CNN that takes place in Peru. Those people are just a little twisted in my mind. The guinea pigs are treated like pets and dressed up and paraded around the town. At the end of the parade the festival continues with the killing and cooking of the guinea pigs. The "pet" parade now turns into a cooking and eating celebration.

Now I am well aware that some cultures eat different animals than we do but I still find it very strange that a town would treat an animal as a pet then slaughter it for a festival.