Hmm, I guess the FIDNDC steering committee overlooked the possibility of an infinite board.
Bill Smythe
I had had that same thought before I began this thread. But then I realized it would only be a “drawing disadvantage” – having the opposition would be a disadvantage only because the player having the opposition would be forced to give up the opposition, if that makes any sense.
Does anybody have any really nice No-Draw puzzles? It appears that two of my three were badly cooked by excessively simple solutions.
As for the various infinite-board varieties, it might make things more interesting if there were also infinitely many pieces and/or pawns. 
Bill Smythe
But can you even have K+Q+Q on an infinite board?
Hmm, good point. No pawn can ever reach the last rank, since there is no last rank. So no promotions.
Unless maybe there are infinitely many queens in the starting position.
Bill Smythe