The only thing block chain adds to any problem is when you don’t want a managed good or service to be under central authority or if it can’t be under a central authority (the later situation is probably more interesting). Crypto currencies make some sense (though I like my currency backed by the full faith and credit of a government, personally). However every other situation I hear of I wonder why someone couldn’t just manage a central service. Chain of trust on crates of produce? Supply chain professionals have solved the problem of authenticating sourcing of goods quite a long time ago (especially when laws required them too). Personally I think the one benefit that people don’t talk enough about is cases where the block chain can provide its users perfect forward secrecy on their transactions against the ledger, though again you don’t really need the block chain to do that.