IIRC, in New York it’s illegal to absorb sales tax on individual items because by law it’s a consumer tax collected by the business and explicitly not a tax on the business itself, but - and it’s a pretty big exception - anything sold as a bulk good can include the tax in the price. That includes things like liquid fuels, grains or candy by the scoop in the supermarket, loose sand/gravel/salt/whatever for outdoor use, and things like that. It’s been a long while since I had to set up an ecommerce site for New York though.

That makes too much sense, which is why it won't happen. Though I'd be all for it.

I don't think this will happen in our lifetimes. It's like not moving the day hour ahead/behind twice a year. A wholly stupid idea that will likely never be fixed on the federal level because of inertia.