Not completely true, as I only learnt about a week ago, back in the day an anonymous appartment of the Red Army Faction was discovered exactly because they paid

Not completely true, as I only learnt about a week ago, back in the day an anonymous appartment of the Red Army Faction was discovered exactly because they paid their power bill with cash - something that's highly uncommon (even then) in Germany.[1] So yes, buy stuff with cash in shops and/or if there's enough other people doing it. [1]: german article: http://www.spiegel.de/spiegel/print/d-13519259.html http://www.spiegel.de/spiegel/print/d-13519259.html