
Yes and no
I agree it could be an indicator of work ethic.
But it could also be an indicator of time optimization.
As far as job capabilities, depends if core courses or not.
As far as using it for offering salary, hey, corporate culture does a lot of stupid things. It stand in for someone actually doing a detail interview and judging the value of the individual. It lets HR apply a formula.
So if you want to play the game, and you find yourself applying to these types of companies, then deal with it.
But I've never worked for a company that did this, and I've been part of the hiring process for about 25 years in 7 companies, not little ones usually. I've easily interviewed hundreds and offered about 30 positions, or approved for another department to hire them.
Not once did we care about GPA.