To me, if you cannot define what collecting is all about (to you at least) then you are not a collector. Everyone's definition will vary slightly, as it should. We all have different reasons, different stories, and different aspirations. I enjoy the history, the hunt, and the trophy. I collect coins because they are beautiful and have seen the world in a way and a time that I can only dream of. I stack bullion as a hedge and to diversify my portfolio.
One or two obols if I remember correctly. I wouldn't be carrying a bunch of tetradrachms just in case Charon is short on change!
http://www.cointalk.com/t201812/ For some coin collecting is the ultimate in conspicuous consumption: A complete set of $20 gold coins, the best early dollar collection, etc.. My guess is that they get tired of looking at their best set after a few years and decide to auction it. Some coin clubs are largely focussed on quite affordable coins and collectibles. Others have wealthier members who like to see more scholarly forums for their interests.
Coin collecting is whatever you want it to be. For me it's -- A. And no, I don't necessarily buy into the "coins are a bad investment" argument any more than I buy into stocks are a bad investment because the S&P500 is lower than it was 12 years ago. With either, you just have to buy the right ones at the right time for the right price. Although I appreciate the history and aesthetics of some coins, I don't have the "collector" gene. I lean toward collecting experiences and memories rather than any material thing. Actually, the older I get the more I'm divesting myself of "stuff". So my own personal definition of coin collecting is simply the same as my collecting of stocks or bullion, only on a longer time frame. With stocks I'm looking 3 months - 2 years out. Bullion, 1-5 years. IRA/401K, 5-10 years. Coins, 15-20 years.