I was visiting my local pro shop yesterday and noticed a ball in the "used", "discounted" "buy it cheap" rack of the shop. The owner will make some inexpensive stuff available as everyone doesn't have the money to buy the newest ball. So it works out to the benefit of both the shop and the bowler.
The ball that caught my eye was one that I had never seen in person before, an Ebonite Gemstone. It was the purple one and undrilled. Before I sold off all my stash, I would have jumped on it.