Another user, who posted the note to Imgur, said the woman whose car was hit was their grandmother.
"My Grandma has terminal cancer and this was left on her car today near Chermside Shopping Centre complex," they said.
"She's worked all her life and adopted kids from all cultures.
"She's a proud Anangu Pitjantjatjara Yankunytjatjara woman and ashamed this treatment is still happening to her even after being part of the Stolen Generation."
People had a furious response to the note, with some calling for the owner to contact Chermside Shopping Centre and request the CCTV footage outside the complex.