Raze,
Can you ask around the shop if these over powered enemies are a glitch or intended to be super hard. I never like to assume things as the word assume is an acronym in "Assuming makes and ASS out of U and ME."
Man kind used to assume the world was flat... boy were there wrong!
I second this. I would also be highly surprised if it isn't a bug that was just a low priority to fix / will be fixed along with the upcoming difficulty overhaul but not important enough to single out / hotfix.