I recently did that with a Virgil Finlay drawing... though I didn't technically steal it, I just re-drew his original image in my own way. I, however, still add 'Apologies to Virgil Finlay' on the poster.
I wanted to make something more iconic, something smack dab in the middle of the poster. Not a scene, but a thing. I feel like most of my imagery has some kind of story attached to it in some way, whereas this just 'is'.