What you're describing is just an adhesion contract, and it doesn't happen only with consumers. For instance, around here the supermarkets have a lot of bargain

What you're describing is just an adhesion contract, and it doesn't happen only with consumers. For instance, around here the supermarkets have a lot of bargaining power over their suppliers, and make use of rather lopsided adhesion contracts (e.g. the supermarket decides whether, how much, and for how long to discount the product and the supplier pays for the discount).