Another way to make money is to coupon. There are many sites on the web that help you correlate grocery store sales with coupons. Couponmom is one and it is free. I get most of my coupons from the Sunday newspaper or you can buy them online. Depending on what coupons are in the paper, I buy anywhere from 20 to 40 newspapers. (There is a grocery chain in my area that sells newspapers 1/2 price) Cutting and filing coupons is a lot of work but it pays off. I file them in envelopes marked with what they are, what it is worth, and expiration date and then filed by category in plastic containers. (Example: aspirin, body washes, hand soap, etc.) Every week I pull the expired envelopes and toss them.
I'm telling you all this because I then take all my loot to the flea market and sell it.
When I don't have a flea market day I'll throw up a yard sale. Kmart every 6 weeks or so has double coupons up to $2.00. That makes a lot of products free. I always walk out with a cart full of health and beauty aids, shampoo's, razor blades, etc. for nearly nothing.
I couldn't tell you how many thousands of dollars I have gotten in free products over the years.
It is a win win situation. The grocery stores get the value of the coupon plus around 8 cents extra and that makes their sales go up, your customers who do not want to be bothered with coupons get the product for less than the store sells it and you make a few bucks for your trouble. I always wondered why people will complain about the price of gas, utilities, etc. but will not use a coupon.