As far as I know, it is up to the seller to choose how they want to be paid. Most choose Paypal exclusively due to its convenience, security, etc. Plus, of course, eBay encourages it because they own it. 🙂 However, some sellers do accept other methods.
(Plus - Paypal often has a slightly better exchange rate, at least for Cdn to US than MC, for example)
FYI - those of us volunteering our time to answer questions here are just buyers and sellers like you. We have no influence with eBay, its policies or procedures. Nor any line into Customer Service. You should contact them directly or, better yet, eBay Corporate, if you have an issue.
