rose-colored glasses
Stop showing your customers the origin of your cheap meat through your rose-colored glasses!
1/3

Solution

Maybe you know this phrase "to see sth. through rose-coloured glasses" ​This means a happy or positive attitude that fails to notice negative things, leading to a view of life that is not realistic. So I think this will fit perfect to the task. Lidl and Aldi show their customers not the realistic. They show things through the rose-colored glasses. You can use this keyvisual as Illustration or as real Image (Photo Collage with Stock photos). It is also good for guerilla street campaigns.

Campaign Scaleability

You can make posters & animated gifs with the glasses effect. And augmented reality glasses to show the suffering. And you can print pink and green paper-glasses (solar eclipse) or made with LED lights. And XXL glasses to put it over the Lidl and Aldi signet. The idea behind is easy to understand.