Libraries' scarcity mentality

When you download an audio book from your library's website now, you get put on a waiting list if one person has already downloaded that book in the last 2 weeks. A much better system would be to allow unlimited downloads, but with the price escalating as the demand increased. The first download of a given book could be free, but the next download of that book could be 50 cents, next could be a $1.50, etc. and then prices could fall back down over time as the downloads expire.