You can buy a gallon of water for less than a dollar. That's what I do. It's more cost effective than a two liter of pop for a buck fifty.
What city do you live in?
I have mixed feeling s about this.
I think the government should incentivize healthy food more than it does. As it stands, the reason we have so much "corn" in our food is because the government subsidizes it. This is taking the opposite approach, trying to punish those who want to engage in unhealthy behavior. It's not that different from the tax on cigarettes.
At the same time, it doesn't apply to bodegas, which, if you live in NYC, are probably where you get a lot of this shit anyway. Especially in areas we would classify as a food desert, I can't see this being a huge loss since there are no real restaurants, no access to healthy food to begin with.