NGC4Lib has a long thread on whether or not libraries are immune from, or subject to, normal “market” forces.
I have to say, it’s a little depressing that the question is even being asked. We have customers who give us money, and every so often they decide whether or not it’s money well spent. And when it’s not…well, they take their dollars elsewhere.
The catch for libraries (as well as most other not-for-profits) is that the customers (those who give us money) and the patrons (those who take advantage of our goods and services) aren’t the same group, at least not in a 1-1 correspondence. It’s a representational relationship, and one of the challenges of running a library is that the values of the patrons and customers don’t always line up.
But don’t pretend for a moment that just because libraries are often unable/unwilling to vote with our feet that either our patrons or their representatives with the purse strings aren’t willing, even eager, to take the money and put it somewhere else. If you can’t justify your budget and your existence, don’t expect either to last forever.
OPAChyderm 
Well said. This dichotomy between the “people that give us money” and the “people that use our services” can cause a huge disconnect in marketing. And often does.