If there is any, the reason is The Money.
No! Of course The Authors' rights over their intellectually forerunning, pioneering project... However, Our beloved Founding Father Archangels could really benefit also economically...
If releasing Frontier, and Frontier: First Encounter to the Public Domain (with relevant Trademark clauses)...
Few more people would play those damn buggy games.
Imagine T-Shirt sales...
- Elite Plus Arkkienkeli