This is assuming you are buying goods that are outside of the country. Most consumption weekly is things like food, drink, disposable items and not things like computer hardware which is refreshed every few years normally.
> There is a reason why rich prefer tariffs over a progressive income tax.
I am not rich and would prefer Tariffs over income taxes (I am in the UK). I would rather save the that gets taken every month from the taxman and I could afford to buy myself a nicer property. I could also make the conscious decision to make sure I purchase items produced in the UK which presumably for food, drink (at least) I would wager is produced in the UK and thus would be cheaper than things produced outside of the country.
As for progressive taxes they actually make it more difficult to earn more money even at a near minimum wage. When I worked at a super store (Tesco) many years ago, If I worked a few hours overtime, I would go over income band for that month and it effectively made working that shift a waste of time. I am including my time to commute which was a 30 minute cycle and not wanting to have to stack onions. So I didn't bother working overtime as a result. Neither did many of my colleges. Granted I normally would get a check back at the end of the year from HMRC as I would have over-payed for the year, but when you are living month to month, I would always prefer the cash in my pocket as the end of the tax year is an eternity away in comparison.