From the actual article:
> The payment processor keeps 0.35% ($0.35), then pays 2% ($2.00) to the cardholder’s issuing bank and 0.15% ($0.15) to Visa. The 2% is the interchange fee, commonly known as interchange. The 0.15% is the network assessment fee. 8
In other words, they get 0.35% of every transaction ... and it does not require anything close to that to maintain their network.