Yes, if you don't tell me you did the murdering I would accept the money. Your actions are on your conscience.
> But if I work hard as a nurse, exchange some of my hard-earned savings into Ether, and donate it to you, you will refuse because "there is no uncertainty about where they come from"?
> I'm confused. How are you certain that the USD donations are clean money, and certain that the Ether must be dirty money? I guess just the vague association with "crypto" is enough?
I have moral responsibility for my actions. Due to the way a blockchain works, I can't accept or withdraw your Ethereum donation without contributing to the blockchain with a transaction fee. I can't fault you for putting it there, that is a matter for your conscience, but I can fault myself for accepting it.
> Just admit that this is about ideological purity and nothing else.
It is not about ideology at all, but about conscience. I believe ideology is almost as harmful to humanity as the blockchain.