I just learned something interesting: tipping restaurant workers is a legacy of Jim Crow. Early in the last century, the National Restaurant Association was formed, and one of their innovations was to replace wages for predominantly Black women working in restaurants with tips, so they could continue not to pay their workers. This was later codified into federal law by Roosevelt explicitly excluding restaurant workers from the newly-mandated minimum wage law. They tried it on with the railway workers, too, a predominantly poor Black class, but unionization pushed back and it was never legalized. The practice was further legitimized in the 60s with the creation of a legal “sub minimum wage” for tipped workers.
However, seven states have long had laws guaranteeing fair minimum wages for restaurant workers (including WA), and since the onset of the pandemic restaurants have been forced to offer more than mandated minimum wages for workers to counteract the massive resignations in the industry.
For more info, see the article here.