I have been toying with this idea for years. Having a website where I list my grocery list and then with one click it tells me where I can find the products the cheapest today. I have also noticed for a long time that even if the shop belongs to the same group of companies, they do not ask the same price per item as it depends on the demographics of the area. A Checkers in one area will have a different price than a Checkers in a "richer" area. Did you notice that?
My problems:
1. I can't program a website, but I'm sure that can be overcome.
2. How to get the pricing updated daily. Now if the shops co-operated that can be done every morning as they have the pricing in electronic file and that can be uploaded daily, but will they do it? Well if the site works the way it should, it will as they will want you to buy from them. PnP has this pricecheck where they compare prices and show you how much you save on your till slip.
Then I came up with a better idea. Almost something like uber. Get the people that shop to update the pricing via cellphone. They choose the store from a list, choose the product and put in the price.
So if any one want's to take this forward, contact me. Lets give these buggers a kick under the butt!