Paul,
The casino chip collecting hobby is very similar to all the other hobbies out there, like collecting baseball cards or memoribilia. If there is a chip out there that you really want, you would be willing to pay more than face value for it. A baseball card only costs pennies to produce but the ones from years past are expensive because there were fewer of them made and there are fewer of them in good collectible condition today. This is true about casino chips also. Many of the older chips are commanding high prices because of there age, condition and how many of them are thought to be in existance today. There are some chips that some of the collectors who were pioneers in this hobby have that there only known to be 1, 2 or a very few to even exist. This is the simple supply meets demand problem in economics. Supply is low and demand is high so people are willing to pay a lot of money for those really scarce chips. I think this post is quite generic in content but this is what I have learned in the year and a half of collecting casino chips. I am not ready to fork out hundreds of dollars for one chip right now, but if I had the money to do so, I would. The price that you will pay for a chip goes back to how badly you want the chip.
Luke