Trying this Purina free cat food thing

A couple months ago, I signed up for this Purina Myperks site using a code a friend sent me. Every day I've gone in and clicked on things, had a couple of friends accept my invite, and I've entered two UPC codes from cat food I've bought. Wow, there really ARE internet pyramid schemes for everything! It took me about a month to get to 30,000 points, which is a coupon for up to $15.99 off of a bag of cat food. Pretty cool. I requested the coupon on July 1, and they mail it, and I haven't seen it yet. I'll update when it shows up. Still, the program seems pretty easy and I can't imagine it wouldn't be legit. If I can get a free $15.99 bag per month, that would cover about half of my cat food expenses, which would be awesome. Here's my link if anyone wants to try it.