A (Kinda) Funny Joke

A man is hungry and spots a hot dog stand. He walks up to the vendor who happens to be a Buddhist monk and orders a hot dog with everything on it.
He hands the monk a $20. bill.
He enjoys the hot dog and then realizes he never received his change back from the monk.
He walks up to the monk and asks, "Where's my change?", to which the monk replies, "Change, my son, can only come from within."