Is it considered acceptable or unacceptable to use currency as a measure of utility?
Utility functions as ordinarily used are not a measure of well-being comparable among people, but a representation of preferences. Moreover, preferences could principally be elicited from choice experiments.
A utility function assigns real numbers to alternatives so that one alternative is preferred to the other if and only if it is assigned a higher number.
Now in many situations, one can use so-called &quot;money metric utility functions.&quot; Start by holding prices fixed (this should already tell you a fundamental limitation of the idea.) For each commodity bundle $x$, let $u(x)$ be the price of the cheapest commodity bundle at least as good as $x$ according to the preferences. Under some assumptions, this gives you a genuine utility function $u$ representing preferences and it gives you actual dollar values. But the natural interpretation depends crucially on prices being fixed.