[Skunkworks] Banks vs MPesa

Safaricom has pretty much taken over the e-commerce service sector in Kenya.

From paying (water/elec) bills, online purchases (local) and even air/bus/train reservations. What is it exactly that is lacking within the banking sector such that one cannot go online and pay for any/all the above using their debit/credit card yet they can do it with mpesa which has only existed for a fraction of the time that banks have been in existence?

-Billy