Question

Why does the pilobolus use such an explosive method to disperse its spores??

Answer 1

So it does not land in the zone of repugnance, a zone which prevents the spores from being consumed by the cow. (zone of repugnance is a zone of which a cow will not eat grass, this explosive dispersal of spores will allow the spores to be eaten by a cow and later pooped out to grow into a beautiful fungus)