There are plenty of forms of monetization that don't require users to pay money (ad supported being the obvious one), and there are even more forms of monetization that require the users to pay money, but not pay money for an app (think Uber or Grubhub), and while it does seem to be the case that Android users are less likely to pay money for an app than iPhone users, I'm not aware of any sign that they are less likely to pay for a physical good or physical service through an app.

But clearly iPhone is not in that position, I agree!

I think parent's point was about free apps that are just access points to a physical world service like airlines, hotels, Uber, Yelp, OpenTable, etc. I do suspect iPhone users spend more per capita generally because they're probably a wealthier demographic than Android. But I also suspect that overall marketshare is more relevant to the companies developing the apps in this case. (It's also somewhat beside the point though because everyone in this position is going to have an iOS and an Android app at a minumum.)