Why does Mybitcoin, or anyone, have to offer you recourse?  Bitcoin is cash for the Internet.  Would you walk into a corner store and pay cash for a candy bar?  What is your recourse there?  If the vendor took your money and then told you to buzz off, what would your recourse be?  Call the cops over $1.50?  What would happen, do you think?  In the end, you would be out your money and a candy bar, and would simply never trust that vendor again.  Don't send bitcoins to untrusted vendors.  If you get screwed, tell people about it, and name names.  Sometimes the risks of getting defrauded is just part of the costs of doing business.  There are steps you can take to limit those risks, but none of those things are intergrated into Bitcoin, nor should they be.