Some cool observations - you've brought up some points that I never even thought of before
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- Regarding the lack of people saying Merry Christmas except on Christmas Day - I can only think that it's a bit like wishing someone Happy Birthday... you would only say it to them on their actual birthday, not for a month or so beforehand... so I guess, Christmas Day is thought of in the same way - it's Jesus' (so-called) birthday, so we only say it on the actual day. That way, it's special when we do say it because it means it's 'actually' Christmas
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- I don't know what it is about people not introducing themselves to each other... when I started university, I spent an entire week talking and hanging out with the girl who would become my best friend... and I never even knew her name! It was kind of awkward when I had to ask what her name was a week into the friendship
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- You mention that there are so many self-service tills in UK stores, but I remember seeing them in stores in the US a few years before they arrived in the UK.
- Doggie bags: a lot more restaurants in the UK will give you doggy bags now than they used to, but you're right, it's still not really a 'done' thing. A few years ago, we were eating Sunday lunch in a Wetherspoons and my brother asked for a doggy bag. The response: "We're not allowed to give you one, in case you go home, reheat the food, get food poisoning and then decide to sue us!"
- Movie popcorn: I refuse to pay the extortionate prices they charge for popcorn in the cinemas , so I've never actually noticed whether it's freshly-made or not
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- Bagels: I've never had a real New York bagel, although I have eaten bagels in the US and much prefer them over there. I think it's just that bagels are pretty new to the UK and no one really knows what they are supposed to taste like, so they just do their best imitation of them... a bit like Mexican food in the UK
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. One of my colleagues will bring in a whole bag of bagels to work and then he eats them all dry - I have no idea how he manages it!