It gets complicated. In New York, food and clothing is not taxable. The gotcha is “prepared food”, which is taxable.

For example, an unsliced bagel is food. A sliced to order bagel is prepared food and taxable. A system like you describe would be insanely complex.

Here’s NY guidance on when a sandwich is taxable: https://www.tax.ny.gov/pubs_and_bulls/tg_bulletins/st/sandwi...

As insane as that is, I think it makes the sales tax more progressive, as poorer people spend a high proportion of income on food. I am always struck when I travel to a place like South Carolina, where the property taxes are low, but people with nothing are paying 9% sales taxes on food.