I don't think that's quite what people usually mean when they talk about diminishing marginal utility. Granted, "marginal" was missing from the parent comment, but I gather that was the phenomenon being discussed.
Diminishing marginal utility implies that you gain more utility by acquiring your first penny than you do acquiring your hundredth. Now, at such small levels of money, you could certainly argue that almost nothing is for sale at 1 penny, but once you get above the level where the disutility of carrying around a coin is dwarfed by the utility of the money itself, diminishing marginal utility applies pretty well.
Diminishing marginal utility implies that you gain more utility by acquiring your first penny than you do acquiring your hundredth. Now, at such small levels of money, you could certainly argue that almost nothing is for sale at 1 penny, but once you get above the level where the disutility of carrying around a coin is dwarfed by the utility of the money itself, diminishing marginal utility applies pretty well.