See, whenever confronted with strangers trying to get me to sign up with their charitable organization or give them money or what have you while I am in my travels, my gut response is just to tell them 'sorry, no' and be on my merry way. The problem is, this totally cuts out any opportunities for me to harass these people trying to harass me.
Case in point: while walking in the cold the other day, and the smiley college girl in the Greenpeace jacket holding a clipboard asked me if I would like to do something about this weather, I just said "sorry, no" and kept walking. What I should have said is "HOLY CATS, Greenpeace has a Weather Dominator?!" and then accused them of collaborating with COBRA, a ruthless terrorist organization determined to rule the world.