Stop getting ripped off by Roman restaurants

I understood the scam to be the huge bill which didn't reflect the weight of the raw seafood hence my previous reply..
Having read the subsequent replies the OP seems to confirm that at #11.

Strangely I can buy by the pound here in metric Germany. "Pfund" or 500 g gives the same result.

Italy uses the metric system. In a shop, you ask for un etto di prosciutto (1 hg, 100 gr). Kg, hg, cg, mg etc are abbreviations of the metric weight measures commonly used and taught in primary schools.

Strangely I can buy by the pound here in metric Germany. "Pfund" or 500 g gives the same result.

Metric would be much improved with more of this ... we have the litre, which is fine, and the metre is not bad, but we have no word for 1,000 grams other than kilogram ... we could use "pound" to mean 1 kg, and I think we could steal "foot" to mean 300 mm, and "half a foot" for 150 mm and so on. A "block" could be 500g (of ham or cheese), a "chip" could be 250g, and a "pint" could be 500 ml, 50 cl, 5 dl.

It's really only the crazy yanks who keep terms like foot and pound in their archaic currency.

Haha ... I love a good nut-fudge rant in the morning - especially a papist one! I wonder who our "new" friend really is?

TV Sizes, like Tablets, Laptops and Phones, are in inches, due to packaging for the North American market, as they are the largest consumer of high end electronics. LOL

Probably all true ... but I expect there's a bit more to it than just international marketing: some imperial-to-metric transformations have been relatively easy, and universally adopted. But there are outliers still.

No-one here in regular conversation (let alone writing) talks in miles or degrees Fahrenheit or stone (14 lbs) for human weight, or pints or gallons or cubic inches - all gone. Even slightly less intuitive ones have too - car economy isn't in mpg, it's universally litres/100 km (so the smaller the better).

But some remain very stubborn indeed. Property above suburban blocks is still universally advertised in acres, whereas small blocks are all in square metres. Car tyre pressure is still measured (and thought of) in psi. Strange. And there are many other weird anomalies.

I guess it comes down to the guys and gals in the advertising / marketing departments, and they make a call on whether there is the slightest advantage in keeping the archaic measures, versus the zing they would obtain from using the more modern metric.

There's a common "scam" in Canadian supermarkets, where they advertise prices per pound, but charge you per kilo. So you see apples on sale for, say, 3 dollars a pound, but when you go to pay for them, the price on your receipt shows 6.62 dollars per kilo, and shows the weight of your apples in kilos.

Okay, it's not really a scam. It's just confusing.

Fruit and vegetables are still sold by the pound in Hong Kong. There's a special Chinese character for "pound".

In Taiwan and China, the same word is used for different weights. If you buy "one jin" of strawberries in Taiwan, you will actually get more strawberries than if you buy "one jin" of strawberries in China.

Restaurants which charge per weight are an opening for scams, the world over. I remember in Indonesia once going to a fish restaurant and ordering a fish whose price was determined by weight. The fish was weighed in front of me by a guy, and I agreed to the price before it was cooked. As we sat down to wait for dinner, a woman who also worked at the restaurant started berating the guy (in Indonesian, which I could understand) telling him that I was a stupid tourist, and he should have tried to charge me double the usual price...

And why tires are also in Inches, it goes together with the North American market? And you buy in Ireland and the UK a pint and not half a Liter.