"Too cheap to meter" may depend on the meter costing a lot. Perhaps electric meters were a significant fraction of the expense of a power hookup at some point.
I'm not sure there's still capped broadband anywhere in mainland europe, even the UK mostly stopped doing that.
IIRC some Japanese providers cap upload, in the 100s of GB, that's basically just network maintenance.
Residential bandwidth is effectively too cheap to meter, but US ISPs found they could keep nickel-and-reaming their captive audience, why would they stop?
nickel-and-reaming
Server/commercial data usage is often not metered; bandwidth is charged at a fixed price for the provided line, or e.g. a 95%ile (making off-peak data "free").
Water is not metered individually per household in some houses. There is one meter per house, and the cost is split (equally or according to some formula based on people living there or apartment size).
That's not so much "unmetered" as it is "metered using a fixed heuristic for expected usage, that results in the supplier still making a profit† even if you're using 100% of what they provide."
† a profit compared to 100% usage with the relative additional costs of metering. (This is why the price is fixed around 95%—that's the break-even where metering the extra usage would cost just as much as taking the hit on the unmetered 5% extra usage.)
This is definitely not typical in Europe. Typically you'll get a bandwidth cap and have to pay per gigabyte above that. For home use this is not the norm.
Edit: Though reading this again, I was mostly talking about server usage - in which case I don't know of any country that has unmetered bandwidth in practice (this means no FUP either, which is just a fancy way of saying "there is a cap but we can change it whenever we feel like it") in the EU and I have an above average familiarity with the space.
There was no free toilet paper in China a couple of decades ago — either bring your own, or maybe buy it for inflated prices from a nearby attendant.
If you want to talk about things that actually flow, I'm pretty sure using the sewers free during the Roman era — but you had to pay to get it hooked up. A bit ironic since now many places meter for sewage (using the water bill as a proxy).
Low marginal cost of drip coffee certainly enables restaurants to offer "unlimited" drip coffee refills. (Quotes because you might get a nudge to buy something else or leave if you hang around all day.) But deciding to do so is driven to a considerable degree by the prevailing customs/practices. You at least partly get free coffee and soda refills because customers generally expect them in the US.
And on most Burger Kings, at least in some European capitals.
When Di Cleverly and Dave Thiery set up Pluspora as a home for for G+ refugees, the costs worked out (at least for direct hosting, ignoring admin costs) to about $0.25 per user.
Not per month.
Per year.
They're hosting 10,000 users (a very considerable chunk of the active English-language G+ user core) out of pocket.
That's literally too cheap to meter. At best you might aggregate service at blocks of 100, and more likely 1,000 - 10,000 users -- large groups or communities.
One reason mass media turn to advertising-based business models, and all the dysfunction and social malfunction that generates, is because adverts are a tractable scaling and grouping mechanism. They're a hack (though not the only one) to the too-cheap-to-meter problem.
If you could pay $1000/mo for "some ads", that would be unmetered.
But that is because charging the direct users isn't tractable.
Charging users rather than advertisers fails (largely) due to TCTM. Though there are other dynamics as well.