Yeah, I had the same experience - got nailed with the $6 monthly fee, and was told I had received the info buried in the stack of papers I got when I opened the acct.
As was suggested - either do a paypal transfer, or make some small purchases every month. For example - a couple of stops at a grocery store, getting a few bananas, purchased at the self-checkout, one banana at a time.
Be sure to close the acct after 6 months, then be sure to re-open another one, since you're allowed to open one a calendar year.