I became a premium member after a month of geocaching as I felt it was something I was going to enjoy longterm and wanted to contribute.
I make use of the extra features as I have a PDA and prefer the paperless caching to papered, which is more environmentally freindly and fits with the aims of the sport.
I get annoyed from time to time with the server problems like everyone else but it does not stop me going out and caching - just logging them..... I just wait a few hours and try again. These guys do it for the good of everyone else so its not fair to complain openly. I work in IT and know the frustrations they go through, you only hear from the users when theres a problem not when its working OK - Big thankyou guys.
sorry slight rant......
Its down to personal choice - some people dont want to pay because they cannot afford it or feel that they might not stay the course.