I used the grocery game for a while about 3 or 4 years ago. Overall it REALLY is a good program. Totally legit, and while it does require a bit of a time investment, for some it is a lot less time than seaching through deals and coupons themselves. Time is money! So paying for the GG's time, isn't really all that bad b/c w/o the GG you may not have found certain deals.
After a while I quit b/c my youngest 2 kiddos had food allergy issues, and we were still in the process of discovering what exactly the youngest was allegic to. So we had to pretty much make everything from scratch so I knew exactly what was in everything.
Which of course meant no pre-packaged items. But through that experience, I finally learned how to really "cook" (I had never really made much from scratch before that time) and how to save money that way, and also ensure that everything we ate was made from whole foods and I knew exactly what was in our food.
So here we are years later, and we still eat this way :) I rarely buy prepackaged items, just meat, produce, dairy case items, and baking supplies - and there are rarely coupons on those items. My youngest also does still have a dairy allergy, so prepacked items w/o dairy are hard to come by.
So for us, the grocery game isn't worth the monthly fee, b/c we don't buy many things you can use a coupon for. We buy our toilet paper at Sams, we don't use household cleaners (only vinegar - also from Sams), I buy 25 lb bags of flour and bread flour at Sams, and 25 lb bags of rice from the Oriental Store. So I don't need coupons for cleaners or boxed items.
The best way to save money is to cook from scratch, bake your own bread, snacks, waffles, pancakes, muffins,etc ,, cook w/ whole foods (meats, grains, produce) and buy your baking supplies and grains in bulk --- but again, time is money. I CAN do that b/c I stay at home w/ my 4 kids - so I have the time to save money that way.
If I worked outside the home (I work from home), then I would not have time to prepare our family's food the way I do -- in which case I would probably use the grocery game b/c I would need more boxed, pre-packaged, and convenience foods.
So depending on what type of eating habits and purchasing habits your family has, the grocery game can work for you :)
Good Luck!