I have purchased 6-pack cans in Pittsburgh and New York. This year, the cans were not available in Pittsburgh. I’m not sure about New York. Only 2 liters have ever (going back 20 years) been available in the DC/Balt area.
I imagine it has something to do with the regional bottlers, but I can’t understand why Pitt and not Baltimore. Pitt is not exactly known for being a Jewish city, but Baltimore certainly is. I think Baltimore is easily in the top ten in both total Jewish population and Jewish percentage of population.