To my knowledge and to be fair, I don't think they were caught by the Germans. I think that prompted by questions, in essence they caught themselves, identified the breach, and announced it right away. I have no personal knowledge of it, but that's my understanding.
If it had not been identified when it was, I think the danger would have been in just complacently continuing, on the understanding or the thought that they were, in the engineer's terms, “superficial privacy concerns”. The belief was that any data picked up would be so scrambled anyway by the speed at which the cars go by that it would be meaningless. It would not be meaningful data. I think the danger of not identifying it and stopping immediately would have been the continued complacency in not understanding the privacy implications, and of course the more you collect, the greater the risk to citizens' privacy.
Essentially those are the risks, and as we've seen in other instances, the more you collect, the more risk you have of something untoward happening to it. There is a greater risk that it will be leaked or otherwise breached. The risks just compound from there.