Okay, I know that shellac doesn't actually come "waxed". It has the wax
in it and you either get it in its standard form (or waxed), or you get
it "de-waxed".

I've read plenty on the virtues of de-waxing shellac. For example, if
you want to use it as a primer or conditioner, dewaxed is better.

But ... what are the advantages of leaving it in its waxed state? I
assume that there must be some advantage, or otherwise why would they
even sell it in that form?

Jack