But I think the network effects are too strong and we are seeing a pretty normal Pareto distribution. Even if you added 20 new market entrants with good coverage, consumers and businesses would still prefer to have Visa as the lingua franca of payments.
I think it will also be pretty hard to get away from that 3.5% processing fee. That covers a lot of fraud prevention work that credit card companies take on for consumers and businesses. Will consumers be happy to give up those protections and reap back a percent or two on prices? And emerging payment technologies seem to create more opportunity for fraud.