I'm always amused by some mispronunciations that stray farther away from the original than necessary.
My favorite is probably crepe, which Americans pronounce like an almost diphthong-y craype (or crape like grape I guess) when crep (like step) would do just fine and be closer to the original.
But as a native French and basically-native American speaker, I also couldn't really care less about it, or about things like Americans pronouncing the t in croissant, or French people being unable to say the.