Frankly an 80% piracy rate seems a little difficult to believe given how most iPhone users I know use their phones (most use stock firmware, since they're still on warranty, and people have spent up to £800 and don't want to 'brick' it).
An 80% piracy rate doesn't mean 80% of iPhone users are pirates.
Now my math might be little shakey, but let's say, hypothetically, for every 1000 iPhone users there are only 50 who pirate games. If only 5 out of 1000 buys a game, but 20 out of 50 pirates download the game... you would have an 80% piracy rate even though only less than 5% of users are pirates.