I dont want to add anymore drama and ughsgtidhxhs. But a real simple, short of version of a famous youtube video is this:

Employers bet tips will cover the lower wage when evenly dispersed amongst by staff at the end of the day/week. While customers bet if they tipped less or even stopped collectively, then employers would be forced to pay them a living wage above minimum constantly, then eventually stopping tipping altogether since chefs, behind-staff wouldn't be tipped either.

The problem however, is that both sides are 'right' and 'wrong'. You're either helping one person/group now but reinforcing a problem, or your trying to stop tipping but in this moment you just seem like a real beef jenkins.