Investors also have a fairly specific job to founders and employees taking equity vs salary: allow enough needs to be met such that seeking employment elsewhere isn't a temptation/need.

A C suite (and often to developers and pos) position at a startup that has raised funding is likely to experience 1) offers at or above market rate in leadership positions 2) A professional network of people able to afford a certain comfort 3) a stressful or dismal looking event at work.