IMO tipping in its current form should be outlawed thereby making restaurant operators pay their help at least the state mandated minimum wage. Sure the cost of going out to eat will rise to make up for it but really you're already paying those prices anyway because of tipping but at least food workers will be earning a consistent living.
As far as the pizza industry is concerned; they absolutely prey on their help. My mom used to work for Papa John's for several years and then Dominoes for a few years, mostly out of desperation. Both jobs offered absolutely no benefits despite insanely long hours, paid around $3/hr and sometimes something like $.20 per mile traveled when delivering. So people who work in the industry have to get their tips to manage to make any decent money to get by, furthermore since the Great Recession of '08 it's only gotten worse to the point where many pizza joints have a hard time retaining help because they refuse to pay a decent wage and people who order refuse to tip or they actually tip only a few cents. It's also very hazardous work, at least in urban areas, as it is not uncommon to be robbed at gunpoint for pizza if not for money and the major chains prohibit delivery persons from carrying any form of self-defense non-lethal or otherwise. A cop actually told my mom once they he would be terrified to have to deliver pizza for a living on account of how dangerous it is versus being a cop.