America's new millionaire class: Plumbers and HVAC entrepreneurs

There are several tradespeople I know (electricians, plumbers, carpenters) who make more money than I do. But I don't begrudge them that, electricians do work where a mistake can literally kill you, and all of these jobs have high injury rates and will wear your body down much faster than sitting at a keyboard.

Edit: and there are no "open source" tools. You have to buy them, and good ones are not cheap.

Carpenters too? I'm not from the US but this is a crowd I know and talked to quite a bit, at least in western Appalachia. It seemed to me they are shafted quite often, as big companies hire them as subcontractors 90% of the time and underpay them. The last 10% another tradesman/local architect get a contract and hire them directly and they earn almost twice their usual pay but that's a small minority of their contracts.