Anyone who works an honest job to make an honest living is worthy of respect. If it pays their bills and feeds their family and puts a roof over their heads I totally respect them regardless of their field of employment. The work may be hard or dirty or unrewarding (except for their paycheck) but they can hold their head up proudly as far as I'm concerned.
Notice though I said honest - if on the other hand they are lying, cheating, swindling, thieving etc, then all bets are off. For example an honest used car salesman is worthy of respect (and yes they do exist), but a cutthroat, ripp-off scammer is lower than pond scum. Do you understand the difference?
Naturally, this also works in reverse. A CEO of a company may live in a mansion, drive a Mercedes, own a yacht, sit on the board of several companies, but if they are ripping off their employees, swindling their stockholders and gouging their customers, they are also the lowest of the low.
It's not about the field of work you are in or your relative position in the heirarchy, it's about your work ethic and morals.