Calculating the sales taxes is not a simple matter

We've got 50 states, each of them with different sales tax rates. Within each of those state each county, and possibly even cities or other smaller jurisdiction within those counties may or may not have additional/separate sales taxes. The rates differ depending on goods. When I lived in Pennsylvania with a 6% state sales tax, food and clothing were exempt from the sales tax. When I moved to the People's Republic of Maryland, the sales tax went down to 5%, but included clothing (the rate was recently boosted to 6%). Even within a broad range like food, different things get taxed differently. Where I am currently, milk is not taxed, but sodas are. Any of these 1000s of possible taxing jurisdictions can change any of their tax rates at any time. Some even have certain "tax holidays" on which they collect no sales tax. Here in the People's Republic, they do this for a week a couple of weeks before public school starts for "clothing and school supplies" whatever the hell that means. It is reasonable to expect a store owner in a fixed location to know the tax rates for his city/town, county, and state because that is only 3 levels of confusion.

Anyway, we all expect the New York judges to engage in sufficient mental gymnastics to produce a decision exactly the opposite of the clear meaning of 1992 Case (and its earlier catalog sales precedent) . This case will only be decided once it gets out of the state system.