So what is the location for the book?

There's a Twittering on at present about where  books for YA and children are set in the UK. Well someone asked and someone I know answered the question...and other people went on to answer the question.
And it went on...and on - rightly so - and it made me think.
A lot of books are set in imaginary places of course. That makes it much easier for the author.  It is much easier to write "somewhere in Cornwall" or "on holiday in Wales" or, vaguely, "in London". 
I wrote a book some time ago. It was set on the east coast of Downunder.  The young hero makes a journey from a small place near the coast to the capital. 
I gave it to someone else to read and it was returned to me with the comment, "It's terrific but you can't go from X to Y in like that."
Actually you can. I checked. I didn't do the journey myself but I checked the railway timetables and then I asked someone who was actually doing the first part of the journey to check. Could he have done it? Easily.
It was more difficult to find a believable way of getting a slightly underage boy on to the last train to do the last part of the journey. It isn't a local train he uses. It's an interstate train and different rules apply to children travelling alone. I needed to know about those things. 
Yes, it took some research. 
I always marvel at the amount of research which must go in to even apparently simple historical novels. Get something wrong and one of your readers is bound to tell you. If you get something wrong in present day novels then there will probably be even more people who will pick it up and tell you "that's wrong" or "it's in the wrong place" or "you can't do that". As for the thought of writing serious science fiction....I wouldn't even consider it. I don't know enough.
So perhaps it is easier to set things in the present but in a fictional location? I am not even sure about that. You still need to do research. Can that black haired child really have two blonde parents? It seems a bit unlikely...so where does the child come from? Is there a job which requires someone to leave the house at precisely the same time every morning? 
There are all sorts of things you need to know. If writers set their books in real locations as well then surely they are to be admired?