It gets worse every year but unless you have a trip planned to the US any time soon what can you do? I was thinking of picking up a 7 plus for my uncle but just looked at their website to check the new prices and in the UK the 128gb version is £769 while the exact same model in the US is £579. Some states in the US have zero sales tax so that isn't the reason, it's just sheer greed.
If it's any consolation they do the same to a great many other countries.
It won't end until there is a serious competitor and that just doesn't look likely at the moment. I realise Samsung etc make some beautiful phones, indeed any neutral observer would have to say the Samsung S8 is better looking than the iPhone X, but it's the basic fact that they have an OS that gets used by so many different companies, the same problem that condemns windows PCs, that ultimately undermines the experience and stops many of us from ever moving over.
I'm going to buy either the X or the 8, not sure which. But I really think Apple are pushing their luck - my purchase will go down in their accounts as a successful sale. But over the past decade or so, most times I bought something from Apple I knew I was paying a lot but thought I was getting something so special, so far advanced compared to any other company that I felt it was a fair deal - I really wanted to buy it. Today I will still buy it but my feelings are very different, I essentially feel I have little choice, my 6 plus is struggling, I prefer the OS and am in the ecosystem and rather resent the fact they are just going to cream another £280 from me compared to an American (the iPhone X 256 is £865 in the US and £1149 in the UK).