It reduces use, but the people stubbornly still using tobacco are likelier to be poorer. No peer-reviewed studies are required to demonstrate that it's a regressive tax, any amount of "Think of the children!" posturing notwithstanding.

I'm fine with that. Cost was a factor in helping me quit. Considering the lifetime cost of being a smoker (both in past expenditure and probable future medical expenses) I wish cigarettes had been much less affordable when my parents were puffing away during my childhood. I loathed cigarettes and yet I was in a hurry to try them and sure enough became seriously addicted to tobacco.

Where think of the children == reducing incidence of lifetime addiction and horrible disease. Though I guess you have to pick your priorities.

You pull the child-card to justify discriminated taxation against the poor, but I pull the 47y/o free-willed bummed out waiter card. Shall we start unfairly taxing sugar as well, which is probably a bigger epidemic than tobacco amongst children[1]?

[1] https://www.youtube.com/watch?v=dBnniua6-oM

This is actually being discussed by some politicians, and some are past the discussing step AFAIR.

You forget that a sugar tax is increasingly popular in progressive circles.