Anybody can get an extension, you don't really need a reason.  But the extension only extends the filing of the return, not the payment of any balance of tax due on the return.

If you are a U.S. citizen or resident alien residing overseas, or are in the military on duty outside the U.S., on the regular due date of your return, you are allowed an automatic 2-month extension to file your return without requesting an extension.

Since there is no place on the tax return to "show" you were out of the U.S. I always file the extension - for safety sake.