“Don’t be a turkey.”

How tired are you of seeing this phrase, accompanied by a clip-art picture of a turkey, on Thanksgiving-related flyers?
Some examples from the web:

  • HIVdent.org requests that I not be a turkey this Thanksgiving by handling food safely.
  • ESPN requests that I not be a turkey when I go hunting for turkey. That makes sense, I guess. I should try to be the hunter instead.
  • Science Fiction Romance suggests I avoid being a turkey when writing science fiction romance stories. I think I’d be happy just to not be writing a science fiction romance story. Is that like… alien love?
  • In Tobacco “news” from the Cape: Don’t Be a Turkey – Try to Quit Smoking Now.
    Does anyone know what is so bad about being a turkey, and why it is relevant to serving food, hunting, writing, and smoking? Is it that turkeys get killed? If so, why don’t people just say, “don’t get killed”?
    Another question: Does anyone actually say, “Don’t be a turkey”? Or is it always written. I just can’t imagine it in verbal context. “Dude, you gonna come out tonight?” “Naw, I think I’m just going to stay home and read.” “Oh come on man, don’t be a turkey!”