I think you nailed it there, honestly. Cities and counties, and even some states, have little to no ability to affect change in how skewed and fucked up the farming and food distribution system is. The mess of subsidies and tax breaks and weird legislation is too tightly wound - and too many scared people know that and yet rely on it for their livelihoods - that you can't fix the problem at the core: The way farming is funded. So you gotta do what you can do... incentivize better choices at the consumer end of the food chain. The is already happening at the grassroots level, with non-profits stocking gas station coolers with fresh produce and veggies, and school programs teaching kids about what food actually is, and how to make healthier food choices. Those are all positive incentives. But it is a two-sided coin. You need to make disincentives that drive people to make better decisions. You are incentivized to get a driver's license because it is useful ID, and you can use it as proof of who you are to get a loan, pick up a prescription, etc. It also allows you to operate a motor vehicle. It does not give you the RIGHT to have a motor vehicle. If you operate it in an irresponsible manner, then the cops take your license, as a disincentive. Taxing poor food choices is already done for cigarettes, liquor, and any number of other things. Nobody prevents you from buying them. The price is raised to incentivize you to think twice before getting an addictive and health-damaging substance. The base social contract of any society is that you will behave in a manner that is compatible with the society at large, and not put an undue burden on anyone else. Everyone gets enough, if people are responsible and don't take too much. But then you throw in addiction and brain chemistry, and you need to give some people an incentive to avoid those addictive substances, so they don't put an unbalanced strain on the system. Where the money goes? Honestly, who fucking cares. It's a sin tax. The whole concept is for it to eventually make itself irrelevant. Of course the argument to that is well why the hell don’t we just pay more for it in the first place so the farmers make more money so it doesn’t need to be subsidized so we don’t need to add tax to cover the subsidizies.
I get the incentive idea however I was a cashier at a grocery store where this happens for too many year to believe in it. Everybody is just floating through life paying no attention to anything but sharing memes about the life they’re barely even conscious for. The people buying healthy food don’t realize they aren’t being taxed and the people buying crappy food don’t realize there is an alternative. You give people to much credit.