A shop, that lets you overpay for goods you like, to invest the overpay into the companies that made them.
Would you overpay for your favorite food, like fish, potatoes, milk, rice, or whatever at a 10%, 25%, 50% above the base price, if you knew, that the overpay would automatically buy you shares of the maker of the product, so that in, say, 5 years, would you be able to get it for free, or get the dividends buy it? I definitely would, especially for my favorite products. It would automate my investment into companies that make the things I know I need, without any extra effort of investment portfolio management.
So, it's an idea of a competing supermarket, that buys goods from wholesalers, and through use of membership cards (popular loyalty cards), maintain investment portfolios for the customers. Surely, that type of supermarket would require for it to be a stock portfolio management company at the same time, so, two industries: retail trade + fund management.
Such supermarkets would have a social mission, to help people automate their lives. They would also be educational for kids, teaching them how to never have to pay for a favorite meal again.
Perhaps we could start such a supermarket chain: make money not just for ourselves, but for our customers. The idea is inspired by a previous idea: Consumer Investment Tax.