Never saw it, but I do use coupons. I like using coupons for anything I already buy and check the expiration dates and wait to see if items hit sale prices I'm familiar with. For example, I buy whichever granola bars are on sale for 2/$5 and use the typical $0.55 to $0.75/off coupon, which my grocery store doubles, so I pay between $1.00 and $1.40 for a normally $2.99 box of granola bars (like Fiber One or Nature Valley). I also use them if I am picking a "treat" cereal (anything with sugar) since you can get coupons for that and I don't mind treating my kids once in a while. My last grocery store trip was expensive (my opinion) at $182.91, but I saved $5 in coupons and $4 from the doubling, and we got enough food (mostly) for 2 weeks, including all the dinners we were planning (family of 4). We have had to run by on the way home from work to pick up milk and things like that that we can't store in bulk but go through quickly. That also included enough steak for 2 or 3 meals, enough chicken breasts for several dinners (even with company since we have company once or twice a week it seems). So, yes I love coupons and use them--it doesn't take me much time to flip through the coupon flyers since I do them as soon as my husband brings them home from work and I use them to help plan meals and snacks anyway, which I do before shopping. I keep them on a clip in my purse so if I'm not sure about something I'll keep it handy in case I see it on sale when I'm out. I do use coupons.com and redplum.com for online coupons, and a few other sites, but find the smartshopper coupon printer no longer works on my computer (it is installed, but tells me it is not).
I have never gotten $500 worth of groceries for $5 or $6 though. If you're looking for another way to save on totals, angel food ministries can save you between $28 and $32 on a box of food (I did the math with my favorite grocery store out here) and you can pick up the boxes of food from a local church. I still haven't ordered from them but have friends who love it.