[davem]

I think Tolkien kind of 'assumes' the reader will feel more drawn to the 'good' side. In an interview he spoke of the underlying morality of the world he created:

Did this alternative creation worry Tolkien, a lifetime Roman Catholic? It did not seem to. I had remarked to him once that, despite the absence of organised religion in his mythical world - no priests, no temples - his peoples still behaved well. Yes, of course, he said, there was "what theologians call natural morality, natural duties and courtesies - ".

So Tolkien assumes that attitudes which are often held up as part of the 'Christian' underpinning of his creation are in fact anything but - they are the result of 'natural morality, natural duties & courtesies - when a man refuses to strike an enemy when he's down, that sort of thing'.

It is this 'natural morality' that Tolkien plays on - he assumes the reader will be drawn to the good side not because they are made more 'attractive' & exciting, but because whether the reader is 'religious' or not they will be, by their nature, more attracted by the good side - in fact, their behaviour will actually seem more 'natural' to the reader than the behaviour of the bad side.

Hence, anyone who is attracted by the bad side is (according to the theory Tolkien espoused) is going against their own natural inclinations.

Of course, Tolkien could have been wrong.