Somebody has to do it. We wouldn't have the civilization we have if we had no scientists. Similarly, we need teachers, caretakers, stay at home parents, and somebody has to repair the phone lines and pave the roads. If every person on the planet simply pursued the maximum pay career available to them, we wouldn't have much of a society at all.

You should certainly be aware of the financial sacrifice you're making to do socially impactful work and consider this in the decision calculus, but I don't think you can say zero people should ever make that decision.