Most people have no interest in getting all techie just so they can send/receive quick cheap payments. Most are perfectly happy to trust a centralised institution with their small change, and to go about their day not caring about all the geek stuff behind it. Horses for courses. The great thing about decentralisation is that anyone who wants to can participate in providing a global public good, but that doesn't mean everyone on the planet should be expected to do it. Most will just want to utilise it as needed and get on with their lives.