I have no idea if this is within the rules, but another option could be to use the "Gift This App" function to generate paid, non-expiring promo codes instead (send it to yourself). You'd incur the 30% App Store revenue cut this way in addition to any sales tax.
That's an interesting idea. I wonder what Apple would think. On one hand, they still get their cut. On the other hand, they like having full control over the experience. On the gripping hand, how could they even stop it?
Since apps are ranked in the App Store by revenue and number of apps sold, buying copies yourself could also be seen as ranking fraud, so I'd assume Apple wouldn't like it.
