Schöner Schein has a double meaning. It can just mean "a pretty bank-note" (Schein is short for Geldschein (bank note) in german) but it can also mean "prettified, not showing like it really is). My idea is to show a modified euro-bank note, with a new image. Instead of buildings/architekture it will show a suffering pig or other livestock. The customer is encouraged to take a closer look a the price (bank note) to discover the real cost (e.g. suffering animals) of his purchase.
Greenpeace against cheap meat
Activists pay with modified bank-notes at the targeted supermarkets.