I think if minor enhancements can make a film better then its fine. Its when they go overboard and add things needlessly.
Again, with E.T. In the beginning when he's running away from the humans and gets lost, in the original he was just on a rail and it went straight through the foilage in a straight line. Sure it worked, but it didn't look too realistic. This part of the scene was replaced with CG of him hopping and scurrying away, which looked much better and made him seem more animated and alive.
This is a good example of CG used appropriately. We should also consider the budget of some films. Newer movies these days don't always have a good budget and have to work within their means, and that usually forces them to use CG since theres not enough money for physical materials to make things as real and life-like as possible. I don't blame them in cases like this. Its when its within their budget to be able to afford something more genuine, whatever that is, and they don't take it, that they missed out on a good opportunity to make the film better. You can really only make a movie once, so you have to make it count.