I just don't predict much of a following for another station with the same programming as KBLE.
The 5 mV/m signals of the two do not overlap. And in noisy metros, 10 mV/m is likely to be the strength needed to overcome man made interference.
Perhaps the KBLE signal is weak for the Olympia area, but I just don't see a major conglomeration of people wanting to hear this kind of programming.
I'm pretty sure the buyer knows this, but they likely feel that the cost of the station is justified by the possibilities of furthering their goals.
I think its important to consider how much of the population is Catholic, and how many people belonging to the population would be interested in this type of station.
There is 2004 data about the Seattle Archdiocese:
Diocese rank 15
Catholics 904,000
Population 4,755,500
Percent Catholic 19.01%