Makes me wonder how many customers would be willing to pay 10 or 100 cups of coffee up front to fund their channel. I don't expect direct channels (where you don't pay any routing fees) to become a big thing.
They wouldn't open a direct channel because they can pay via existing channels... but it should be emphasized that funds in a channel aren't "paid". If they create a channel to the coffee shop with 100 cups of coffee worth of funds, they can use those funds for whatever still. They can close the channel to move the funds offline or they can pay payments to other people using those funds, routing across the coffee shop.