This is confusing correlation with causation. You can look at this data and say "Apple has the best customers" or you can look at this data and say (less sensationally) "Apple doesn't sell phones for people with little disposable income". In fact, the more accessible the Android platform is to low-income people, the more "valuable" Apple customers will appear by this logic.

I very much believe that, if you control for income and other demographic factors, you will find that Apple customers are willing to spend more on apps. And probably in many cases it can make good business sense to make iOS-first or iOS-only apps. But this data is insufficient to make any conclusions about that.