HN threads on tipping turn me into the Joker. This stuff is so hard for me to read.
Yes, you can trace tipping back to demeaning pre-enlightenment service worker dynamics. But you can do that with almost anything. Talk to a socialist Google worker about the morality of their $350k comp package. As I have learned the hard way trying to convince a local polity that zoning is fundamentally racist (it is), to confront a system you have to address what it is today, not what it was historically.
And yes, tipping is widely abused, especially in the fast-casual and low-mid casual segments of the market. You want to set a N0% plus-up over minimum wage on front of the house jobs? I'm here for it. We're going to put a lot of restaurants out of business together with this plan --- the most abusive sectors of the restaurant business operate on the knife's edge of profitability --- but maybe that's for the best.
In high-end casual and fine dining, though, tipping has nothing to do with master-serf relationships, or really any kind of exploitation. A fine dining server's comp package looks a lot like that of a sales account manager: an untenably low base with a variable comp package on top. The reasons are the same in both cases: because of principal-agent problems. A flat salary for servers (the "living wage" system) breaks incentives: if you're going to make the same money whether the restaurant is packed or empty, why would you ever want to work a Friday? Put differently: tipping gives service staff exposure to the gross upside of the business, and aligns that exposure to the server's own agency in the business --- managing the customer relationship, monitoring the products being delivered from the back of the house.
This is part of the reason that expert servers quit when fine dining restaurants try to flip to no-tipping models.
People complain about how manipulative or stressful tipping is. I think that's pure applesauce. Divide the check by 10 and multiply by two. Or double the sales tax. Your check probably has the 15-20% line figured out for you already. You go into an American restaurant knowing you're on the hook for the tip, like adults in America have done for generations. If it's a scam to fool you into thinking prices are lower than they are, we've all had more than enough time to metabolize and work around it.
Tipping subsidizes owners. But everything you spend in a restaurant subsidizes owners. You're where all the revenue in this industry comes from.
This not the system I would design if I was the Pope of Chili Town. But it's not the moral calamity nerds like us make it out to be, either.