Hi,
Countable nouns are associated with the notion of 'completeness'. A living chicken is a
unity because it is complete (normally) we can distinguish one chicken from another one, so we can count it, we can say a chicken or one chicken. But what happens when we refer to the food, the flesh? In that case chicken becomes 'matter', 'substance' with different shapes and weights it loses its identity. It ceases to be a unity. We say 'I had chicken for lunch.' when chicken is the food we ate. We would say 'I had a chicken for lunch.' to mean that we ate the whole animal, which is possible but not very likely.
The thing with money in its general sense is that it is an abstract notion. Money is not thought of as a unity in itself. We do not count one money, two moneys. When we say we count money we mean that we count currency which is the measurement for money. We count one dollar, two dollars, three dollars and so on...
Hormones can be thought of as unities because we can distinguish one hormone from another.
Well, I hope I helped. But maybe someone could explain why and in which situations the plural form 'moneys' is used. I heard that a couple of times. It is obviously an exceptional case but I would like to know its meaning.
Bye.