I think it is unfair for any of us to attempt to make a financial decision for anyone else. To me, right now, the member fee is not much. But there have been times in my life that it would have seemed very high (even the $3 monthly fee).
I think this is generally a good philosphy. In this case, I want to add a small, 'yes but...' The very nature of this game involves a $200-$400 GPS and a $500-$???? computer. Hiking is free. If someone is trying to decide between a $3.00 contribution to geocaching.com and eating, maybe its time to sell the gps unit and just go hiking.
Also, the entire sport would be almost impossible without this site which is 1) high quality 2) heavily used and therefore increasing expensive. I think the current system is a pretty good compromise. Free, a voluntary system that provides small perks for people who contribute and a contribution scale that starts at $3.00.
As I get ready to place my first few caches, I am leaning toward making them member only for the first couple of months, mostly because I want to put something fairly nice into them for the first person to find it. But I would rather not have such a thing plundered. Recently, someone in my area put a new gps unit (!) in for the first finder and it was gone when by the time the first person to log an entry go there.
As long as they are opened up after the first few logs, I don't understand the negative tone about members only caches. Thoughts and further education appreciated.