it's only been the last few years that Catholics are trying to catch up
Actually, the inertia has been building, and the results may have become more noticeable over the last few years, but various Catholic groups have been into buying radio stations for much longer.
Almost 20-years ago I was contacted on behalf of a group of wealthy Catholic businessmen who wanted my opinion on a bundle of eight or nine AM radio stations scattered in cities around the country they had been offered. The stations were to be used for non-profit Catholic "Propagation of the Faith" programming, as well to provide a way for the Church, its teachings, and its news to be more available to local Catholics in their daily lives. Simply, it was to be a Catholic version of the Protestant broadcasting model.
This group of guys knew a lot about business and making money, but not much about radio. What I saw was a bundle of high end of the dial directional AM stations, some with very tight patterns, that took the bulk of the signal over areas of their metros where Catholics weren't likely to live. This was right after deregulation and it looked to me like during the buying frenzy that followed the FCC ownership rule changes, somebody had taken these low potential AMs in as part of deals for good signal FMs, now didn't know what to do with them, and was trying to unload them all as one group.
IIRC, the total purchase price was to be about $70-million, which these guys thought meant they would be paying for "premium" properties and signals, but that was an era when some single big market FM stations were being sold, and re-sold, for even more.
The actual money wasn't a problem, I think they were going to pay cash, but they were concerned about the value and the ability of the signals to accomplish their goals.
When it comes to Radio Maria, and its ability to "afford" the purchase of a NY area station. They seem to know what they are doing, when it comes to the "Propagation of their Faith" offering it online, with SCA, HD, and even selling the receivers at what appears to be cost. It's not likely that an FM license could be available to them, but, at today's prices, all but the top signal AM stations are probably within their financial reach. There are, probably, a lot of older wealthy Catholics for whom Radio Maria is a comfort, I suspect enough of them could be talked into helping to make the purchase of a NYC area station possible, if there isn't enough money in the non-profit's bank account already.
That said, given the repetitive nature of most of their programming, they might find digital audio players, some with speakers, that they could pass out to their prospective audience that would play the programming on demand. You have to wonder if they need to transmit it fresh 24/7.
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