Throughout the 80s and early 90s Madonna had a number of images and identities stick in the minds of the press and public. Many of which she crafted but this one was thrust upon her.
The original idea for this song and it’s video was widely misinterpreted as Madonna being a fickle gold digger.
The video concept has Madonna playing an “actress” playing this role in a film with in a film. We see her character as soon as she’s off camera, return to being a regular gal who likes the simple things
This was lost by most of the press looking for a quick hook or image tag for Madonna as result she started being referred to as the “material girl” and the moniker stuck.