When I load up a patch in EWQLSO they are always start off set to zero in the panning box (which is centered). So, I'm guessing they do not automatically pan themselves.

It's "automatically panned" as in, the samples are stereo, and the instruments were recorded in position. So even with the pan knob at center, basses will be towards the right, violins to the left, etc.

That being said, you'll still get sound on both sides (due to the recording hall's reflections), and so sometimes it helps to push them a little further to the side if you wanna clear things up.