Gary this is a curious application of Newton's First Law. A portion of it states "...an object at rest tends to stay at rest, unless the object is acted upon by an outside force."
Your Fiero has, with the exception of occasionally shoving it about, clearly been in a state of rest for a while now. Strictly speaking, the drivetrain is not in the car at the moment, and may therefore be loosely considered to be an "outside force."
However this particular outside force was in no condition to act upon the body at rest the last time I saw it, so why the heck do you need a braking system?
On the other hand, having a functional parking brake would be rather appropriate, given how much time your car spends parked.
Shhh, what's that? Why, I think it's the sound of an angle grinder preparing my headstone!