You can easily overwork devs, and while their salary is higher than others a difference between 60k and 120k salaries is less than 60 employees to do manual work and 15 to automate it.

Plus when devs create a digital item that can generate a profit nearly indefinitely they are viewed as cost productive to MBA types. Versus janitors where for some reason we dont see a value at all in cause of no immediate profit from their position.