Yahweh speaks of blessing the people freely as if he were selling food and drink to needy people for free. (See: [[rc://en/ta/man/translate/figs-metaphor]])
There is a sense of irony in this statement since a person usually has to use money to buy something. This emphasizes Yahweh's amazing grace in giving these things freely. (See: [[rc://en/ta/man/translate/figs-irony]])