Charge 99 cents and hope it goes viral!
One question on my mind is whether the stats are legit. If it's not some quirk in Apple's reporting system, maybe someone is maliciously hitting the link to the 'site of the day'. Wonder what the logs for that webserver look like - is every user agent an iOS device as expected?
I haven't spent much time digging into the iOS app pirating community, but my expectation is that users are less likely to pirate if there's a free version of the app. What exactly does prompt someone to crack a 99c app and make it available to other users? Why would someone go through the trouble to get it that way when it's so cheap?
And everything is pirated. I once had a friend of mine hand me a pirated copy of the PDR (the Physicians Desk Reference on CD). I still have it.. though it's out of date by now.