Zen and Consumerism

The Zen Master is visiting New York City from Tibet. He goes up to a hot dog cart and says, "Make me one with everything."
The hot dog vendor fixes a hot dog and hands it to the Zen Master, who pays with a $20 bill.
The vendor puts the bill in the cash box and closes it.
"Where's my change?" asks the Zen Master.
The vendor responds, "Change must come from within."