Now something I noticed that is related to keeping a price book are the membership-required stores and warehouses. Too often people are misled into thinking they are getting better prices there, when in actuality they are forgetting to include their membership price as part of their cost of food. Let me give you an example.
Let's say there's a family that is spending $200 a month on groceries. They purchase a six month membership for $60 at a warehouse, and find they save about 10%. They currently spend $1200 every six months on food. 10% would be $120, less the cost of membership is $60. If they purchase all of their groceries at the store, they will save $60 on the cost of their food in that six month period, but only if they buy all their food there, and few people do that. As this family starts to approach the 50% mark, they lose their savings. Speaking with people who have purchased such memberships, many of them also find they wind up purchasing larger quantities and lots of non-food items that they hadn't planned on getting. This also hurts their budget.
In most cases, you can save more by being what I call, "a disloyal shopper." Companies are very shrewd at calculating how offering membership can improve their over-all profits and they will fool the majority of their customers into spending more. Keeping a price book in most cases will save you far more money on groceries than joining a commercial warehouse club.
Another trap well meaning shoppers often fall into is buying large packaged deals, such as purchasing a side of beef. Though the sales pitch may look like an excellent financial deal on the surface, usually the customer is not considering the energy costs of the freezer, or if they buy a freezer, the cost of the freezer itself. But one of the largest expenses of buying meat in bulk, is that we tend to greatly increase our consumption of it, which in turn increases our food budget. There is also a greater chance of waste when purchasing membership in farms where you receive bountiful vegetables at the end of the season.
The exception to memberships is this: often membership in a food co-operative store or co-op group will save you money. Co-ops are non-profit organizations, run by the participants. In my local food co-op, for example, you can purchase a one month membership for $4 or two hours of work and they will give you a 20% discount in exchange. This is a great deal. If I spend only $20 at the store in a month, I will save money over purchasing the food there with no membership. There are additional savings, too, because even at full price the food is much less expensive than in commercial stores.
There are also informal groups of people who get together in co-operatives to purchase from food distributors directly. This allows them to buy at wholesale prices. Generally, the group will make one monthly purchase and they must have enough to make the minimum order for free delivery. You need to decide what you want ahead of time and submit your list to the organizer by a certain date of the month. The order is then placed, and the truck will arrive (give or take a few hours) on a particular day. Arrangements for individuals to pick up their orders, varies.