All of that is nonsense.

I worked for 2 corporate retail chains that would send the stores the price labels for sales and we would print out a file for other tags.

In a quarter, most labels would be replaced and they would send irregular price changes every week. We would spend probably 10 man-hours a week taking down and putting up labels under typical operations.

Items don't generally move far or often, except for rotating display spaces at the ends of aisles for promotional items where every tag changes. Every few years they might make radical changes to item placements, but they tend not to because it confuses customers.

There is no reason to exclude the tax in the price labels except for tradition and/or concealing how much you will actually pay with the tax added. Most people know what the taxes are in the area they shop and will just round up to the next dollar or add 10% if they are on a budget.

Bring on wireless electronic price tags that show the price including tax.