Wayne:
Geocaches can be quite complex to decipher; some are camouflaged, wrapped in riddle and enigma...even if given the precise coordinates, some complex cache games can be quite difficult to uncover, indeed.
There are caches with all kinds of bonus / swag items, like solid gold coins, expensive electronic toys (small enough to be hidden), gift certificates, highly sought-after tickets to sports events, and cash (some donators have to beg geocachers to take the items, even if they have nothing of equal value to replace it with! Geocachers are honest to a fault).
I'll bet there are high-stakes geocaching games being played all around the World, with chaches ranging from million dollar bearer bonds, valuable diamonds, Rolex watches, wads of cash, etc...out there.
Other genres of geocaching may involve self-imposed mysteries to solve: ie. finding an extremely desirable ancient ruin site or sites (or, a Lost City hidden in the jungles or under sand in the Middle East, ...somewhere around the World: site the recent book: Jungleland), talked about, but utterly hidden by the handful or one "in the know". The twist is: the "cacher" being a dead and extinct civilization for 1500 years. Whazoo and I played such a game over many months, and won. A trip report was posted on it roughly a year back. The title of the report and content did not mention or intone a "geocaching adventure", however, this was really what this adventure was in essence. Massive investigation went on behind the scenes, using all kinds of technology to find these places (you can't even imagine).
For 99.99999% of geocaching participants, the motivation is getting out with the kids, and having constructive fun, all the while developing critical thinking in the children...
S-