I too struggle with the idea of sponsoring people doing things they want to do anyway.
However, if money ends up in the hands of charities, irrespective of the motives of the individual participants, isn't that a good end in itself?
Also, I'm pretty sure that the "cycle costa rica" trips usually require the participants to (1) cover the cost of their doing the trip and (2) raise a minimum amount of sponsorship. In other words, if you sponsor them, you're not paying for flights, etc.
On the whole I'd rather people gave their time to charities by volunteering rather than went on "cycle costa rica"
Quite. Or, if you have no time, give cash directly. And, like TJ says, don't always choose the "cuddly" ones.

