A consenting adult pays another consenting adult with more experience to do a life threatening task together. One dies. How is this not okay? What are you expecting? For people to never climb Mt Everest again?
In the USA, it's illegal for me to pay you to kill yourself. The issue isn't as cut and dry as legality anyway. Just because something is legal doesn't mean it's morally justifiable. So yeah, there is a world view where paying people money to risk their lives to advertise your buttcoin is immoral.