Too late to edit my comment, but here is one example of going above and beyond for this business:

Uncommon Apps should create and maintain a pdf document with fair, useful information about competing podcast apps that do not use the subscription business model.

When someone complains to Uncommon Apps about the subscription model, if Uncommon Apps cannot change the person's mind (which will be the usual case), then Uncommon Apps can offer to forward a list of alternatives.

This would allow Castro support tickets to end with something useful. Uncommon Apps is losing this sale regardless, but at least there is some reputational gain.