I don't think it's a stretch to assume that the Ferengi really do have a well organized military force. There could be a lot of profit in it - being in the space service could pull in a hefty salary, and protecting the shipping lanes and trade routes would also be very profitable. That being said, we do know that there are Ferengi who like things other than pure profit. For instance there's the Eliminators - hired killers - who are viewed as dangerous psychopaths because they enjoy killing in and of itself, more than the profits gained thereby. So perhaps the military are viewed the same way - as aberrant because they enjoy serving the Ferengi state itself, more than any money they might make.