If, as you say, it would cost more than a station could ever recover to stream, why is it that the number of stations that do not stream shrinks every year, and those that pull there streams are likely to be streaming again within a few years?
It's an investment. If you read the earnings reports from radio stations, the only good news they have to report is digital revenue.
If all these companies do is focus all their attention on a declining business, at some point it will go to zero,