When Stealing isn’t bad.
Graphic design, or commercial art, doesn’t have to be as strictly original as visual art. 
“Stealing” imagery creates a common visual language that can be better understood (sometimes subconsciously) by a greater audience. Designers should get to know people’s personality types and social groups better to understand what visuals they will and won’t react to.
While visual art often gets a pass in introspective contemplation, graphic designers should always be aware of the visual language that is being used within the local community to better communicate with the end user.