Most people are familiar with plagiarism when it comes to the written word. But plagiarism comes in many forms.
Many times, creative people are plagiarized and their work is used for the gain of a larger purpose. That purpose usually is a big business that does not feel the need to credit the individual(s) that created the work of art.
I have been a victim of this and I know many other that have as well. In the case of artist Retna, instead of the Gasteneaus hiring the artist to create the art piece used in the image, they had a fake imitation made.
This happens all the time in creative fields, but for some reason if it is not the written word that is being plagiarized society does not take it as a serious offense.
The bottom line is, in any form of work the creator is due the respect, compensation and credit for the work that they create. Anyone that does not respect this, does not have integrity. Everyone deserves the right to get paid for the work that they do and to be acknowledged for their creativity.