Replacing it wouldn't protect them from infringement lawsuits, and a 30% stock downslide because of a 0.021% outlay on their $100B cash hoard is a little too insane even for a conspiracy theory.
Why not?
So the choices are:
* Have a long and involved court case that you will almost certainly lose, where the press will continually poke you about the obvious and direct comparisons to the Samsung/Apple suits.
* Pay compensation/licencing fees, have the story become a non-story in a day or two, carry on using great piece of iconic design.
No brainer.