This week Target is offering a $5 gift card when you buy two bags of Purina catfood, which happened to have a $2 off coupon on Facebook (explaining my new facebook fandom) and I thought, hey, that seems like a pretty good deal. So I printed off my coupons and headed to Target today to get some. When I got there though, I realized the bags in question were 3lbs (tiny) making $5.59 each seem like not such a good deal. But I drove all the way there... and I figure Willis and Tyra are worth it, so I went for it. One of the keys to couponing is multiple…