Exactly the reason why I always make sure to use the machines when I am departing from an airport that has them. Luckily so far no airline has yet managed to lose my VW green slip but given this completely outdated and somewhat IT stoneage system of working with manually handled paper slips, it is probably only a question of time ... Most effective and hassle-free solution of all would probably be to have a dedicated international departure zone (like in all the European airports) with your departure automatically computer recorded