[WhoBeI]

I've been thinking of something similar.

I'd get a few different signs from random organisations like doctor's without borders, red cross and some other popular ones and then I'll setup on the town square. Big ass signs and maybe a little pamphlet with the details. I'll let everyone know what a fantastic contribution to world peace I'm doing and that I will hand over all their donations as soon as the organisation they donated to gets in touch with me.

I'll just send the organisations a mail informing them that they now have a business relationship with me that I refuse to let them opt-out of. They probably won't mind...

Stop being stupid. Clear your database and implement opt-in.