Much would have more

Some people, though they have a lot, are never satisfied. The ruling passion of an avaricious man is to add to his riches.

Oliver Goldsmith wrote in his long poem, The traveller:

As some lone miser, visiting his store,
Bends at his treasure, counts, re-counts it o’er;
Hoards after hoards his rising raptures fill,
Yet still he sighs, for hoards are wanting still.