Chub me up
The default response for the larger person when asked if they would like to pay that little bit extra for a larger drink and fries.
Patron: "Burger, fries and a full fat coke please."
Vendor: "Would you like to supersize that meal?"
Patron: "Chub me up"
Vendor: "Would you like to supersize that meal?"
Patron: "Chub me up"