Unfortunately, the Supreme Court recently ruled in favour of American Express, saying businesses are not allowed to pass higher charges of accepting AmEx to con

Unfortunately, the Supreme Court recently ruled in favour of American Express, saying businesses are not allowed to pass higher charges of accepting AmEx to consumers with a surcharge. (AmEx's agreement forbids merchants from charging a surcharge). While not directly analogous, the Supreme Court believes that agreements by duo/tri-poly players mandating businesses charging specific prices (or the lack thereof), don't cause consumer harm.