Coin flip on them still being tap water from a warehouse two blocks away.

Source? Because I doubt this very much. Bottled water, much as the companies selling it to you would like to say otherwise, is a commodity. And as a commodity, it benefits from economies of scale. Coca-Cola, eg, is going to bottle all of their water in a few massive bottling facilities across the country. Generic brand grocery store water is going to follow the same logic - the store will either own or contract out their water bottling to a company with just a handful of facilities across the country which specialize in bottling water. Is it just tap water? Yes. But the bottling facility chooses the tap water they use carefully - after all, no one is going to want to buy water that has too much sulfur or calcium. And while they're at it, they're going to make sure the tap water is actually safe to drink. Sure, multinational corporations would like to actively kill you so they can make money on your funeral expenses - but they hate getting sued even more. And if you poison 10,000 people with unsafe drinking water, that's a hell of a class action lawsuit - which is why corporations have armies of lawyers dedicated to ensuring that this doesn't happen.

saw a 2 litre of soda for a buck fifty at a Walmart in rural Idaho an equivalent water on the other side of the isle was three bucks

I just checked. A gallon of water on Amazon is $1.37. And that's with the convenience of being delivered straight to your door within 2 days. At basically every grocery store I've gone to, water is about $1 per gallon. I don't doubt that there are some places where this is true - but I've never seen it.

I will also note that neither I nor no one I know has ever been noticeably affected by drinking either tap water or bottled water. To the best of my knowledge, the problem of toxic drinking water only exists in a few places in the US, and those places are well documented.

The US is quite literally unraveling at the seems but the rich and powerful don’t want to do anything about it.

Ah, yes, the doomer rhetoric. Wouldn't be Lemmy without it. This is the worldview of the terminally online. Go out into the real world, and you'll see most people are doing pretty okay. Sure, they have worries and challenges - but almost everyone is clothed, fed, housed, and drinking clean water. The economy is getting a bit worse, but most people still have jobs and can afford the basic necessities. Try going to an actual developing nation with an actual non-functioning government, and there you'll find... well you'll actually find that people are still doing mostly okay. Because at the end of the day, people are generally resilient and will find solutions to problems the government fails to solve. A good, functioning government can help out a lot, and I'd certainly prefer that the US government was better... but the US isn't some kind of failed state. That's just doomer nonsense.