Meat and drink in this phrase has two meanings, which appear to be independent of each other. Either, to be a source of support or pleasure or, to be a simple and routine matter.

It isn’t clear which of those two meanings is intended in the earliest known use of the phrase – John Frith’s, A boke answering vnto M. Mores lettur, 1533:

“It is meate and drinke to this childe to playe.”