American tourists are often alarmed when they travel around the world and find the conveniences and niceties they are used to at home suddenly aren't available.
Accustomed to polite customer service, spacious stores offering a plethora of choice and wide open roads, the fastidiousness and overcrowding of Europe and Asia can prove pretty eye-opening.
US Reddit readers were recently invited to explain their biggest culture shocks on leaving home and the results were as enlightening as they were entertaining.
Here's our selection of the best answers to TJBull's question for the Americans of Reddit: "What is something you didn't realise was typically American, until you went abroad?"
1. Being friendly.
The lack of upfront social warmth was a big one.
"Being 'friendly' to an extent. I checked in at a hostel and walked into the lounge area where people from all over the world were just chilling," wrote dude_with_amnesia. "I kinda introduced myself to the whole room, and someone goes, 'you're from the States, yeah?' And I'm like, 'yeah how'd you know?' They said, 'only an American will walk into a room of strangers and introduce themselves to everybody.'"
One of the major things that I noticed was that smiling and being friendly towards strangers was considered bizarre.
"In Texas, I was used to smiling at people, asking for directions if I needed them, and being friendly towards strangers. I learned very quickly that smiling at someone on the Tube, or asking someone for directions on the street immediately makes someone think you’re trying to scam/rob them or you’re crazy."
"I was struck by the extent to which nobody talks to strangers in northern Europe," added badass_panda. "Even in big cities in the US, people will talk to each other sometimes in line, on the subway, etc. Not deep conversations, but it isn't weird to make casual conversation."
2. Good customer service in restaurants.
Etiquette-related differences were even more apparent in restaurant settings.
"Going out to a restaurant. In America, you are seated ASAP, and then they bring you drinks, appetizers, entree, desert and then check as quick as they possibly can (if it's good service) for a total time of 45 minutes to an hour and a halfish," Chorche412 attests. "Staying past this time is seen as a bit rude.
"In Europe, going out to eat seemed to be more of an event that you slowly enjoyed for a longer period of time. First, they you bring you drinks and an appetizer for the first hour. Then the second hour is the entree and desert. Then it's more drinks for another half hour or so. I don't know if it's because we were American but it seemed like the wait staff everywhere we went was annoyed that we were rushing them, when we just thought it was bad service and didn't understand the routine."
The lack of free drink refills was also a cause of consternation:
I just wanna drink a ton of water alright?
3. Tasty junk food.
When it comes to what's actually served, those differences are even more apparent.
"When I visited Japan, even some of their sweetest desserts pale in comparison to how much sugar is in American food," willbo2013 offers.
Cheese was also greatly missed.
"My British friend makes fun of me for how much cheese I use in my cooking," says Iximaz. "Doesn't stop her from inhaling my potato casseroles, but there you go."
And then there's soft drinks.
Root beer is apparently disgusting and an offense to most of the worlds palate.
This poor soul got into trouble ordering "biscuits" with their KFC bargain bucket in the UK.
"I was worldly enough to know that 'chips' meant 'French fries', but 'biscuits' in the UK are cookies. My fat ass tried to order fried chicken and cookies. I am positive someone over in the UK is still telling this story at parties as an example of how disgusting Americans are."
Nothing is ever given away free outside of America because, deep down, we in Europe know the customer is always wrong.
Americans answering on Reddit were particularly annoyed by the lack of free public toilets.
And then there's this living nightmare, experienced by doublex12:
At a buffet in Germany, I had to pay for ketchup.
5. Spacious supermarkets open all night.
Americans apparently have little time for easing themselves down the narrow aisles of a Tesco Metro in search of the last box of Frosties.
"How large grocery stores are here," offered wtjax. "My wife is not American and we lived in China and were in Hong Kong all the time... they had large international stores that were great and she didn't really grasp the size of American grocery stores till our first week in the USA and there's 150 feet of cereals on one aisle."
The lack of all-night shopping options was also an annoyance.
It's weird not being able to buy random sh*t at 4am.
6. City blocks and wide open roads.
The layout of our towns and transport networks was another surprise.
"It wasn't until I studied abroad in England and got a complete blank look when I asked someone how many blocks away the library was that I realized using 'block' as a measurement only makes sense in cities that were largely pre-planned and built on grid system. AKA: not many places outside the US."
This user was unnerved by the lack of "massively wide roads/lanes":
The whole of Ireland made me feel claustrophobic, but when I got back home the roads felt like way too much wasted space.
7. 24-hour air conditioning.
Americans like their air-conditioning on all the time and cranked up high, especially in the balmy southern states. Good luck in Arizona or New Mexico without it.
Over here, we tend to be more cost-conscious.
"Keeping AC on 100 percent of the time in the summer. Visited Madrid for about a month to see the exchange student we housed, and found that they typically only turn on AC at Night to sleep or when it reaches a damned 105 deg F."
8. Public drinking bans.
Here's one thing they did like though.
"I doubt this is restricted to America in any way, but when I studied abroad in the UK, the lack of public drinking laws was a bit of a culture shock.
Being able to walk outside with a bottle of beer was very freeing.