the joke is both economical and classist.
Only the poor eat bread with toast and the creator of the wikipedia page failed to include that sidenote.
>Parents spend all their social security money on booze and fags, feed their children bread all day all night because it's cheap. Freeze bread in the fridge to prevent it going off. Children are resorting to culinary experimentation and one such "gemOCchildmindextravaganza" is toast sandwich, when the prospect of either toast or bread has ceased to have an appeal anymore, why not both!
TOAST SANDWICH ™, only in the UK!