Generally when you've got an excellent scripting language already, and lets' face it Python is the Best (:)), re-inventing the wheel is not something you want to do!
I totally agree that re-inventing the wheel is not something you want to do - but trying to use the very best jet engine in the world as a wheel on your car... won't have your car performing well as a car (or as a jet)
Basically, I think some "scripting" options that don't have users typing out code make a lot of sense for certain classes of stuff