Harry Potter and the Washing Up Liquid

I'm reading the Harry Potter series in English for the first time, British English that is. I can say with confidence that I have read these books enough times that I notice when something seems slightly off. I knew that Harry, Ron, and Hermione would be uncovering the mystery of the Philosopher's Stone instead of the Sorcerer's Stone for example, but I wasn't prepared for the numerous other small changes. Dudley gets a "cine-camera" for his eleventh birthday; Dumbledore eats "sherbet lemon" instead of lemon drops; the merry-go-round at the zoo is a "roundabout"; Hogwarts students are always "revising" for exams instead of studying. And my favorite one of all is this gem from Order of the Phoenix,

"'Anyway, it's a nightmare of a year, the fifth,' said George. 'If you care about exam results, anyway. Fred and I managed to keep our peckers up somehow.'"

Whoa, TMI Weasley twins! Now, I have no idea what George says in the American translation, but it probably wasn't anything boner-related. I think I'd remember that. I wonder other little surprises I will find in the rest of the series. I don't think the content was changed, but it is a little jarring that these books that have been such a big part of my life are suddenly so unfamiliar.

In addition to learning such valuable life lessons from Harry Potter, living in Ireland has also led me to realize that there are some huge differences between British and American English. Sometimes I genuinely have no idea what people are talking about. It took me a long time to realize that "tea" can mean dinner. When someone asks what you are having for tea, tea is not always the right answer. Sometimes tea is spaghetti. If someone tells you to bring your togs, that means bring your bathing suit, unless you want to go naked swimming. A press is a cupboard. Courgette, rocket, and aubergine are zucchini, arugula, and eggplant, respectively. I have to remind myself not to get excited when people talk about hockey here because they are referring to field hockey, not ice. Sometimes, I think British English takes way too long to describe items. Why say "washing up liquid" when I could just say "dish soap"? Maybe this is why they shorten so many other words (choc, sammy/sambo, telly, brill, fab, veg). Are they trying to make up for lost time? And then there are some things that just don't make any sense at all, like "drink-driving." That's not even grammatically possible people!