Are US retailers required by law to accept US coins in payment for goods?
No, retailers are allowed to accept whatever in payment for
goods, be that US coins, Chinese Coins, gold and silver coins, or
toothbrushes. A retailer can refuse to honor some or all US coins.
However, since US coins are legal tender, a company cannot sue you
for not paying a bill previously agreed upon in US dollars for
paying in US coins. But at the point of purchase, a retailer can
demand payment in whatever and can refuse US coins.