I worked for safeway years ago, we had 2 women who did this back then. Heres how the couponing works per item.
1-cut coupon from the paper that is a "manufacturers coupon" and on certain days in most stores, every day in some stores, they will double or tripple the value on that coupon
2-club card/member card discounts are taken on top of a coupon as they are offered by the store and not the manufacturer
3-the printed out coupons from previous shopping trips, those are "special" coupons that are not manufacturer coupons either and that is deducted from the cost of the item.
4-if you have a BOGO coupon or something is on sale BOGO and you purchase 2 >many stores you dont have to buy the 2 in order to get the sale price<, it makes them half price per from the very beginning, so youre already starting out at 50% off when you begin with your coupons and other discounts.
5-promo manufacturer coupons are something they send you directly in the mail that are like "cash" toward their item.
I'll stop there and give an example
Ketchup BOGO 2/3.00 >i'm just spitting out numbers here<
this makes each bottle 1.50 each so...
1.50-
.50 coupon-
.50 coupon doubled-
.25 club card discount-
.25 previous trip coupon-
.50 promo coupon from a mailer=
they owe you .50 for that bottle of ketchup!
The one woman who would come in , would rack up about 1200.00 once a month which is about right for a family of 4 and pay less than 100.00!!! I was always amazed, but I always needed to go on "break" when I saw her coming LOL.