I'm not understanding the iOS App Store's algorithm for Family Sharing of applications.
Here's how it works (for me):
If user A shares with use B and wants a free app that A owns, it is impossible to download (the App Store asking for A's credit card security code and then rejects it); but if B wants a paid app that A owns, don’t even use Family Sharing and just charge them.
I'm puzzled by this, since it seems not to be the advertised function of Family Sharing. What am I missing?