Relevant: due to Ohio v. American Express , merchants are generally unable to steer customers from using a particular card. For example if a merchant accepts Visa at all, the merchant has to accept all Visa cards, not selectively choose the lower-fee cards; the merchant also cannot tell the customer to use Discover instead to save costs and only use Visa if that's the customer's only card. This anti-steering provisio…
Later businesses have perfected the art of winning the customer relationship and solidifying their lead with hardball terms for vendors (Walmart), merchants (Amazon), advertisers (Facebook/Google), developers (Apple/Google) and contractors (Uber).