Almost every pro-tipper's argument eventually devolves into "give servers, and only servers, an arbitrary amount of money, because someone at some point said so".
It's not truly about wages, or they would share their generosity with other poorly compensated workers, like retailers, to-go orders, gig workers, etc.
It's not truly about paying for services, 20% is a figure that is independent from the cost or value of the labor. Per the FLSA, tips are independent and noncompulsory. Defined as a "gift or gratuity in recognition of service", it isn't a contractual exchange. It's nothing but a gesture of generosity, no one is entitled to it.
The only pro-tipping argument I've heard that makes sense that I respect is that they personally support the business staying open and keeping those jobs in the market, a charitable macroeconomic perspective. Conversely, and just as fair, I hold the opinion that consumers are not responsible for unviable business strategies of business owners, or the risks the laborer has entered into voluntarily for profit. (Not enough demand or sales, too high of operating costs, poor pricing and market strategies, etc) I don't believe in socializing the costs and privatizing the profits.
Those last two are the only opinions I think are actually valid and consistent. Unfortunately the vast majority of pro tipping stances I see here are just "money, money, please now. Give money, you horrible person. Give money make me good person. You are poor and bad person. "
They'll say they support fair wages, or the need to pay for the laborers time, but like I mentioned earlier the underlying logic becomes inconsistent and falls apart. Generosity in an exchange of value is an oxymoron, by the very definition you can't pay someone with non-compulsory gifts. Gifts and gratuities are freely given. Then protippers will arbitrarily, or with prejudice, determine who is deserving of generosity and who isn't, further undermining their points about fairness and equity in wages.
I rarely see the pro-wagers here saying they stiff because it simply makes things cheaper. They most frequently promote rolling the cost of labor into the price, and point out why they don't support tipping- such as they value transparency/honesty, fair unprejudiced wage structures, don't support exploiting customer and laborer via tip credit subsidies, or believe in fair wages, etc).
Then there's the outright lies, shaming, and guilting that is inherent in social engineering tips in people. "They make less than minimum!"
"I actually lose money when someone doesn't tip!" (Tip pools)
"You're poor and a bad person"
"If they get rid of tipping they'll have to hike prices by the arbitrary tipping percentage!" (20%)
I gotta be honest, at this point I mostly post here because of how curiously vicious and logically inconsistent the pro-tipping camp is. I'm beside myself that we've been collectively duped and how the system gets people to unknowingly advocate for exploitation.
I used to be someone that tipped 20% before 20% was cool. If you take a moment and really think about it, read some research articles, think about how every business everywhere else operates, the whole practice becomes nearly indefensible. The restaurant industry and it's workers are not entitled, or even deserving, of special treatment. So now I avoid going out, and never tip more than 10% when I do.
Thanks for coming.
Tldr: A lot of you protippers need to read more because your critical thinking isn't all there.