It's a philosophy that's been repeated over and over again, both on HN and from those who have been successful in the mobile app markets.

Simply put, Android has an air about it that says "open" and "free". People have come to expect some of the best apps on Android to be free. Apple products, on the other hand, have always had a steep mark-up in terms of price compared to a competitor's product with identical hardware and/or features. Users of OSX, etc, have never had a problem in the past paying for features and programs that come for free elsewhere, and the trend continues with iOS.