In history this wasn't always so. Factory jobs were first considered unskilled positions whereas many service jobs required something akin to finishing school to acquire.
Now we put manufacturing jobs on a pedestal and deem them worthy of high wages whereas service jobs are lowly and what you do until you can get a real job.
Unions, with all their problems uplifted those jobs in the American consciousness. And whatever your politics unions and wage controls are how almost every country in the world guarantees high incomes.