Americans are (generally speaking) louder but far politer in public than Irish people. Even in New York City, which has a reputation for brusqueness I found most people to be pretty friendly.
About the only real metric socket or wrench you need is a 10mm. Everything else is close enough unless it’s super tight.
If the dad has mobility issues, that actually makes a fair bit of sense. A younger person with mobility issues would probably take the same kind of things into account when planning a vacation.
TVs in the bedroom are very common for Americans. There is a great debate among American parents over whether children should have TVs in their bedrooms. There are a number of people who think it’s fine for adults to have a TV in their bedroom, but not for kids (I’m one of these people).
Do you mean the part where it fits on the wrench (ie the square bit)?
If so, that’s an international standard - I’ve never seen anything other than 1/4", 3/8", 1/2", 3/4" or 1". As far as I know, there’s no metric equivalent.
The whole point of American cheese is that it melts well. A very popular kid dish is a grilled cheese sandwich in which two slices of American cheese are toasted in between two slices of buttered white bread. So when an american hears you are going to have melted cheese on toast, that would be there point of reference. English cheese are meant to be eaten and American cheese is meant to be melted in a grilled cheese or on a hamburger and then eaten, that is why American cheese has that horrible texture.
The little square part of the ratchet handle that the socket (metric or standard) fits on is in (fractions of) inches, even if it’s for a metric set. Many sets come with both metric and standard sockets and you want to be able to use the same ratchet handle. 1/4" or 3/8" drive is pretty common for a layman set and then you get into 1/2" or larger for automotive and heavier-duty work.
As my follow-up noted, though, that’s not unique to the American system. It has happened in the UK more often than it has in the US.
Oh, well yeah. What’s that got to do with whether or not the car’s hardware is in metric or imperial though?
Calling the processed, individually sliced cheese “American cheese” might give someone the impression that all cheese made in the US is like that. It isn’t. It’s kind of a quirk of language. You can have cheeses made in the US that are nothing like “American cheese”, and we do. You don’t eat American cheese by itself, at least probably not if you are over the age of 10.
If The Angry Badger had said “grilled cheese”, rather than “cheese on toast”, to his American friend, she would probably have thought of something rather different, and something closer to what he had in mind (though a grilled cheese sandwich would have two pieces of bread, and AIUI cheese on toast would only have one). Two countries divided by a common language.
Nothing. Unless you’re Urbanredneck.
Maybe something lost in translation, or mum and dad being jetlagged. Good to know their response was okay and will let them know.
I’ve had sleeping issues for years and good ‘bedroom hygiene’ (nothing to do with cleanliness) is using it for sleep, reading, nocturnal activities 
and naps only. I hope kids having TVs in their rooms becomes the exception, rather than the norm. Maybe offering them a nice alternative, such as some ‘cool’ bedroom furniture (bean bags, racing car-bed, en-suite, punching bag, night-light, cool morning alarm with wake-up lighting etc) would be a good alternative.
Thing is, in Europe that happens both at the EU level and at national levels, but in each of those polities we’re used to our way of doing it. And there are things which may be at the state/province/canton level in one country, at the national level in another, and supranational if there is some applicable treaty; for example, in Switzerland immigration is handled by each canton, some things have to be the same for all of them (due to treaties with other countries) but the details are still defined locally. Most other countries manage immigration at the national level.
The bits about the American system that I understand intelectually but which I’ll always find confusing is the part where you can have regulations at multiple levels (including multiple taxes on the same concept, such as paying income tax to multiple government entities) and there isn’t one that you can say “ok, so long as I’m ok with this one, the rest don’t matter” (in those European countries I’m familiar with, if there are regulations at multiple levels, you only need to ensure compliance with the regulation that’s more local - it has to include the upper-level ones, so if you comply with the local stuff you are also ok with the higher-level regs); that other where you can have multiple laws on the same subject and as AK84 said, they can contradict the hell out of each other but still need to be followed completely; and the part where if something in a private regulation, contract, local law etc is illegal, the document doesn’t have to get amended - the illegal part is supposed to be ignored (except when not).
Yes, it’s possible that you might have to pay income tax to three or more jurisdictions (federal, state, and municipal—multiple ones at the lower levels if you say work in one state and live in another). Or pay sales tax at the state and county/city level. But these aren’t confusing because it’s largely done for you—unless you’re self-emotes.
Also, there’s a difference between a tax and a regulation. You just pay all the races you owe; they can’t really contradict each other.
Who is going to make you amend a contract and how do you enforce that? The government doesn’t collect and review all contracts.
They don’t need one, they have a tablet.
I hate to sound un-American, but I found Aussies to be the most fun nationality. Us Americans do know how to have fun, however. I’ll accept 2nd place. 
Technically, according to the original definition, “First World” is the USA, Western Powers and allies. The Soviet Block etc are “Second World”. But today, when most dudes use “First World” they mean a civilized , industrialized nation, with health care, some form of democracy, etc.
Well, recently Cadbury bought it. But then Mondelēz International, Inc (a US company) bought them.
In any case, the chocolate is made in various locations, including the USA.
Speak to a group of drunk Aussies in a British, received pronunciation accent and you’ll like find they aren’t as much fun. On a scale of 1 to 10 of geniality, Dutch people I’ve met have all been a solid 10 and Aussies - and I’ve been as polite as possible - have been a 0.
Well I’m a European that pretty much only drinks Guinness and American beers. There’s a lot of non-mainstream stuff that is really easy to get over here and is really, really good. I’m quite the fan of Founders and Anderson Valley. The AV “Winter Solstice” may be my favourite beer ever.
American cheeses range all the way from horrible to excellent. Many Americans don’t even know about some of our best cheeses. Here are some producers I really like:
Cypress Grove (I’m really fond of their Humboldt Fog)
Pt. Reyes Farmstead Cheese Company
The same thing goes for American chocolate: it ranges from awful to great. The best stuff comes from small producers, like Mast Brothers, but there are bigger companies like Guittard that also make high-quality chocolate.