No Stupid Questions

These are known as souvenir plots. Generally, you aren't buying the land, but rather you're buying a contractual right to prevent the actual owner from developing the land.

In much of the USA, the county-level is the administrator for deed recording and for land parceling. Municipalities (eg cities, towns) within the county may have their own zoning rules, and so the question can be divided in two:

1-meter-squared chunks

Zoning laws can enforce minimum lot sizes. For example, an agricultural or business district might disallow plots smaller than 5 acre or 2000 sqft, respectively, because anything smaller would become economically infeasible for those purposes. A legitimate goal of zoning is to make land more economically productive, and plots that are oddly-shaped or impractically small would be counterproductive. The county and cities would also be concerned with tax revenue per area, which scales up with productivity of land (for whatever use is permitted in zoning). Note: I'm not a fan of American-style zoning, which has proven to be quite overburdening and frequently racist over the last 100 years.

But setting aside zoning, there's also the matter of land administration. Subdividing a parcel into smaller lots is common, but since those small lots will take up ledger and deed records at the registrar's office, that adds a non-insignificant cost per plot. Easily several hundred dollars per subdivision, as the process is normally meant for larger real estate transactions in preparation for development.

sell each of those sections to different people

Land transaction costs in the USA are not uniform throughout the country, but they often amount to several thousands just to verify title to land. Part of the problem is that most states don't keep an authoritative land registry that shows exactly who owns what. Instead, title insurance companies make money by assuring the title after a process that investigates the land's title history. Here in California, that history often has to be traced back to Mexican land grants in the 1800s, which is kinda nuts just to sell a small home.

Sure, for a 1 sq meter plot -- which no one should ever buy using a mortgage -- the buyer might not need/want title insurance. But the lack of title provenance inflates purchase prices, simply because people do want to know that they're actually buying something real and it's not a worthless deed.

(as an aside, it's entirely possible in California and other states to sell a deed for land you might own, but which the seller makes no guarantee that they do in fact own. It's kinda like a fork in cryptocurrency, where if the fork is later rejected, then that part of the ledger history is entirely dead and you're SOL. Again, we could really use a central land registry, and not a process based wholly on easily-forged deeds...)

If I wanted to ensure that my land would never be used for a shopping mall or sports stadium

The simple answer is to donate your land to a conservation group, who often buy land to protect it from development. They can and do pay market rates, but if you did want the land to be something that isn't a wildlife preserve, then alternatively, you can sell the land but retain the development rights. That way, you (and your heirs) would retain a choice in whatever future development happens, though how long this deed restriction lasts will depend on jurisdiction. Or you can sell the development rights to a conservation group, so that the party owning the land and the party owning the development rights are separate entities with different objectives.

On that https://cardsagainsthumanitystopsthewall.com/

C.A.H. hired an eminent domain expert lawyer to stall the process, probably you'd need legal advice for your idea.

I think contributors were given a recognition that they helped buy 0.00067% of the land, it wasn't officially subdivided between the contributors nor were they given a share.

No you can't really do it. The government isn't going to allow you to divide a plot into that many tiny ones. What you could do is have a company buy the land and sell lifetime leases for small parts.

It depends where you are...

In Europe (primarily the UK) they sell tiny plots like that because it comes with a lordship.

So you can buy a lordship and token tiny square of land.

But they do that for the title, doing it just for land...

I dunno.

The only way I could see people go for it is if trump sells national Parks and people use this method to maintain it in its natural state.

Depends on your local laws. If there are no municipal or regional laws against it and the zoning allows for it, yes, you could do it.

You could also form a corporation that is owned by a lot of people and use that to buy a regular plot of land, and that would usually comply with local regulations. That’s how strata corporations work.

What you might want is a permanent easement, as is often used for conservation purposes