Escape is escape... it matters little where you go, if you achieve the goal... You are using your own preferences to dictate which forms of escapism actually qualify as quality escapism. Your preferences help you shop when you are at the book store. They mean little to me, I have my own base impulse that make me want to pick up a book and care about its characters for awhile.
The setting of a story makes little difference to me, and it appears to be very important to you. Fine. To me, the story depends on good characters, which can be anywhere and still capture my heart, if they are worthy of it. For me, Tolkien takes his characters to another level, I want to be worthy of them, worthy of being in middle earth, for their duty and honor are unclouded by all that surrounds me... And for a time, I can go there, and be worthy. I put the book down and for a time afterwards, I am a better person.
Escapism? - You bet, entirely and unapologetically . I get the feeling you feel escapism is another smelly fish... It isn't to me. To me, a book that is not an engaging place to escape to is not one I am going to read. Better for me if the story shows me people of great character, but I can care about the sullied ones too, if I am given a reason to care about them. The characters in middle earth are what I love, and I am pleased that they were placed in such an idealic place and time. The author could have placed them anywhere and still made me love them, but if Tolkien had chosen pre-war Hawaii, he couldn't have had them wear the cool cloaks, and that would be a loss.
It sure is important to me. Somehow I can relate more to a story that takes place in, say, South Florida, than in Middle Earth although the latter is a fun read. BTW, I also enjoyed Elmore Leonard because many of his stories are set down here and also because of the quality of his writing. But James Jones overall reigns supreme.