Hi Ernie.....when I was selling, I never did that, but I have had at least half a dozen sellers over the years, send me an item I hadn't paid for yet. I always paid them anyway because otherwise, it is in fact viewed as theft on my part....
Years back I bought a fax machine, got it home, went to put the receipt away in my files and noticed it was charged at $10.95. The real price was $1095.00. Now I could have kept it and been dishonest, but my conscience wouldn't have allowed that anyway, so I rang the store, much to the relief of the salesperson who would have surely lost his job.
Speaking to a legal colleague a few weeks later, he advised me that had I attempted to keep the item, when I knew full well that it had not essentially been paid for, it could be viewed and prosecuted as theft......So...it pays to do the right thing...hopefully your customers will also do the right thing....have you notified them?