Earlier quoted context omitted.
Well, it's no less weird that store running a promotion saying 'If you buy item X today, we will donate one dollar of the proceeds to charity Y.' Also not more weird than the British charity thing of "I'm shaving off all my hair, and that's why you should donate to charity Y." (I suspect Brits need an excuse before they are mentally allowed to do something silly. But any excuse will do.)
I've always been baffled by the British charity thing: You want to ride your tricycle from John O'Groats to Ffestiniog? Fine, do it. You want me to donate to this charity? OK, maybe I'll do it. I just don't see the connection between the two. Please explain the connection to me. You don't actually want to ride your tricycle? But if I donate to some third party, you're going to do something you hate? So you're saying…
Regardless, one of the nice things about the practice is does mean people are at least somewhat committed to a cause they are raising funds for before they go soliciting. It also deals with the irrational part of the human psyche and moves the action conceptually from the person begging to the person trading which can have an impact on how people perceive it.