Originally Posted by
behuman
I did that back in 2007 and ended being if not really arrested, firmly questioned.
The lady at the counter where I applied for the refund called airport police and I was taken for a drug or passport trafficker. It was a lengthy conversation with the police inspector, it ended well, but I was warned not to do it again because it is against the "Hausordnung" to enter the departure area without the intention to fly.
I did it recently and cancelled over the phone without any problems. My set is far from statistic, so I'll wait for FTers with more experience to chime in.