From Essential Hacks (http://www.simania.nl/sdls/eh/sdls-eh.htm):

Buyable food

Buyable pizza (slice), fruitcake (slice), chocolates and crisps. Raw meals not included, since Sims can't be bothered to cook them; ditto hamburgers, which will disappear if there's no BBQ on the premises. Bought crisps can't be eaten straight away, and need the Unsnacker. Pizza goes off extremely quickly.
File: GameData\Objects\Food.iff
Last uploaded: 03-01-2005
Catalogue: Dining room, Misc, Misc.
Version: Hot Date