Ebay won't say it, but under U.S. law a merchant has to accept U.S. coin and currency as payment. Now of course it wouldn't be a good practice to start sending cash through the mail all the time but as a private business they are legally allowed to say what method of payment is acceptable. Just like your corner store can take credit cards if they wanr, checks if they want, first born children if they want. AND contrary to popular opinion, if you want to pay for an item in the U.S. using say 50,000 pennies, the merchant legally does not have to accept that as payment. The law about accepting cash and coin also has a provision something to the effect of REASONABLE AND PROPER payment that keeps you from doing something like that.