I know/knew shift managers in the Los Angeles area (Downtown, South Central, Beverly Hills/Century City/Westwood, and West LA), Oakland/Berkely, Cleveland/East Cleveland, and Atlanta.

They make good money, especially considering that many of them never went to college and some did not finish high school. A lot of them have been promoted into restaurant or regional manager positions.

Salaries at the managerial level start of lockstep but quickly become merit-based, that is, in order to earn substantially more than a standard employee, they must prove that they are substantially higher performing than a standard employee (in the managerial sense, not on an hours basis). A good manager is like a multiplier on his/her employees' work output, so the salaries for managers generally reflect the multiplier they generate.