While it is in the interest of <insert non-ebay buyer here>, to make money. I think this is a prime example for why it's sometimes in your interest to make the transaction despite the drop of 10-30% in profit on your end.
Reason is simple, buyer has access/experience in the market already, and knows where to make the sales that turn him a profit. On the other hand, if you do it, you have to learn it yourself-- Which also equates to work, and potentially uneeded expenditures (like paying for ebay listings).
Just my 2 cents anyhow