You know, you're absolutely right about this. Despite the fact that I know you're right, I seem to be unable to resist nitpicking.
At what point is it theft? If I pause briefly to read the first couple of paragraphs of the headline story? What if I just glance at the headline as I'm walking by? Does it make a difference if the paper is next to the counter and I skim the top story (not picking it up, just reading what's visible) while I'm waiting in line?