Interupting anyone to make demanding questions is rude. Using someone for their knowledge of a place, without having any interest in them as a person themselves is rude. Using someone for language practice is rude. Being made to feel that someone believes they are entitled to an explanation is rude. Walking away once they have had their question answered is rude.
Asking questions with a hostile, unspoken "why are you here?", goes beyond rude into xenophobia and racism. Some of the comments people have been subjected to on this thread are dreadful and I can absolutely see why such comments are "othering".
Maybe it depends on the area of the country which you live in, but I can assure anyone who comes to my little part of Yorkshire - we are interested in you, want to make people feel welcome to our area, celebrate difference, and are really pleased when people choose to become UK citizens. There will always be the odd racist knob head, of course, but those sorts of questions here truly do get asked to all non-locals (I don't have a local accent and get asked, but have been adopted as an honorary Yorkshirewoman - as are people with all manner of accents, dress, skin colours, whether from the UK oroginally or not). It honestly is because we are interested in you and believe we are being polite by taking an interest.
Knowing that it feels so very different to be on the receiving end of it with a non-UK accent, I shall definitely stop asking. I would hate to make someone feel uncomfortable - that's the opposite reason of why I ask. We show our acceptance and welcome through taking an interest. I truly didn't realise it would be seem as anything other than that.
I am so sorry for the crap that so many posters have experienced. It's dreadful. And so sorry for any offence I have caused in trying to understand all this 