The mother sent her son for sour cream. He walks into the store, puts the can on

The mother sent her son for sour cream. He walks into the store, puts the can on the floor: “Baby, what do you want?”
– Mom asked for sour cream.
– A full can for you?
– Mom said yes. She poured him a full can and asked: “Now pay.”
– Mom said
– the money is in the can…