Equating money with value
Equating money with value is a conceptual fallacy in which money is assumed to be essentially the same thing as value -- for example, assuming that if something costs a lot it must be worth a lot, or if someone is making a lot of money, they must have justly earned that money by contributing equivalent value to whoever is paying them.
This is obviously false, as items can be significantly overpriced (or underpriced) for a number of reasons, and many people make far more or less than their services are actually worth.
A secondary falsehood is in the idea that just because Party A finds Party B's services sufficiently worthwhile to be worth paying B a certain amount, that does not mean that whatever work A and B are together accomplishing is worth whatever A is paying B. It may be that B's work is only of value to A, or even that they are together conspiring to deceive one or more third parties in some way.