I know of one use case that seems viable, there is a digital housing market service in my country (called Dias). It uses blockchain to verify transactions related to selling and buying houses. That includes proof of sales, ownership, bank transaction status etc. The blockchain is operated by all the major banks. Their incentive is that it increases the security of the transactions thanks to the immutable digital trail, and also the fact that no single entity owns the "database" so no entity can alter it, or skim service fees etc from the others.