Anyone who considers sales tax to be in any way, shape or form a punishment has a fundamentally broken view of the economy.
(Except for sin taxes, which are screwed up anyway.)
"Punishment" in the sense of "making more difficult/punishing", not in the sense of "disciplinary action".
"I know! Let's punish people for spending money! That'll sure help the economy!"
I don't understand what the hell this fixation with sales taxes is. The "flat tax" obsession can be be explained by an antisocial sense of entitlement, made inexplicable by the fact that 99% of the people that argue for it would be harmed by it ("I want those rich people to have more money, and I should be paying higher taxes so they don't have to!"), but arguing that the best thing would be to actively punish people for spending their money? That shows an even more fundamental lack of comprehension of how an economy actually works, namely by people spending their money on shit. Both sales and flat taxes directly harm the economy, the first by discouraging purchasing to begin with, and both by reducing the purchasing power of the largest demographics. With a sales tax you also get the very real issue of much of your potential income being burned away by spending on foreign soil, unless you impose extremely high tariffs and either tax or greatly restrict currency changing.
You can tax people on money they spend so they take a second look at buying something they don't need...
Which is bad for the economy. You want people spending money, especially poor people. Because, you see, that money goes right back up the ladder to the government, and
everything other than foreign aid (an essentially negligible percent of the budget) goes into improving the infrastructure that the economy runs off of, more or less for free since any money spent is also directly thrown back into the economy. The important thing is the system remaining moving: if people don't spend money, businesses don't make money, which means they cannot afford to keep operating, at least at their current capacity, which means fewer people working, which means fewer people able to spend money, which means even more businesses suffer even worse, and so on. The only thing that breaks cycles like that is the government dumping money into the lower segments of society by providing jobs for people, subsidizing goods that would otherwise be too expensive, and ensuring that the infrastructure that allows society to function keeps running.
or you can tax someone for working so they don't want to work. (Especially if they can get government aid not working...)
If someone is satisfied with the "significantly less than someone can actually live on" amount they'd get from the government enough to not work at all,
then they're not a productive member of society in the first place. They're either so lazy and unmotivated that, regardless of ability, they'd never go beyond the piece of shit "requires no discernible skill" jobs, or they lack the ability to do so. If the government pays them some paltry some so that they don't starve to death or turn to crime, guess what they're going to do? Spend it (locally, since they're too poor to spend it somewhere it won't end up back in the government's hands sooner or later)! Meaning businesses make money, employees get payed, and they all pay taxes, so society can keep functioning and the lowest level of society can be bribed away from turning to crime.
Edit: to make it clear, I'm talking about voluntary unemployment in the last paragraph, not cases where someone is forced into it, by injury or lack of available jobs (and of course, they tend to receive more in aid, as they should, since their circumstances are generally temporary, and it would be harmful to reduce their quality of life (not to mention the morale boost that "even if I lose my job I'll be ok until I can find a new one" gives) while they recover/look for a new job, not to mention that it would reduce their ability to relocate if their current area lacks any jobs in their field.