Piper doors, why the passenger side?

First off, this isn't a post to argue the merits of one-door vs.
two-doors, so if you want to do that, start your own thread...

Why does Piper put the door of the plane on the passenger side? I
cannot think of one good reason. Would like to hear the group's
opinions.

OTOH, I can think of several reasons it would be better to have the
single door on the pilots side:
1. Most flights are solo, so with the door on the pilots side, no
need to constantly climb across the passenger seat.
2. On that same point, I like to keep my charts and headsets on the
passenger seat. Again, I have to crawl over them each flight to get
to the pilots seat.
3. It would be nice to allow passengers to board before the pilot
enters.
4. Again most flights are solo, it seems that egress in the event of
an emergency would be easier with the door on the pilots side.

-Nathan