i don't know if your supposed to wax parkboards but i assume so, make it slide better and keep it in better nick.
If you don't wax, your base will dry out. That said, I don't know much or if there is much difference between waxing for free riding or the park. I've heard lots about edge sharpening but not about wax.
Waxing isn't difficult....somewhat messy with a bit of a time investment, but not rocket surgery. Snowolf had a excellent video series on youtube.