When I'm reading a good book (for me !) I'm immersed in it, almost nothing can disturb me from the story (even very late at night, it's extremely rare I fall asleep on a book !
). It's a real escaping for me, no doubt !
But some just can't do that.
They can't be immersed in a tale that is too foreign of real life.
I have a friend that is reading History or Crime quite a lot, and doesn't go with Fantasy or Sci-Fi, and is always amazed of my ease at immersing myself into this sort of Fiction !
PS : Sorry if my turns of phrases are not exactly correct, not my mother language...
Edit : By the way, my english comes almost completely from my readings, so it's another interest in the reading of various types !