Re: Nor a good solution
And what problem is crypto-currency solving? You can hardly buy anything with any of them, I don't know about this conference but in the past, even many crypto-currency conferences didn't accept crypto-currencies as payment. If you want to pay for something anonymously you could pay cash. If it's a large amount where cash is impractical and you need to remain anonymous then odds are that what you are doing isn't legal.
So other than facilitating money transfers for criminals, what good is crypto-currency?