A ref is part of the pitch - I understand that. But so are players?
A ref finds himself in the six yard box and a shot comes in and cannons of his bonce straight into the back of the net. If he was a forward, he'd have been in an off side position and the lino's flag goes up for offside.
Goal?
It'd be funny though wouldn't it I was with four refs and they were split on this other than he'd never ref again