I do understand, but I preface this by warning you that you will not like my answers.
The explanation does help, and it'll stop us from chasing the wrong rabbits. You're never going to be able to do that. The page and post IDs actually use the same incremental counter (and IIRC, attachments do as well). To change that would require a serious recoding of the entire product.
Now. Obviously you can hide them via pretty permalinks, but you're right in that http://www.example.com/?p=N will continue to work. And you need it to for other reasons on the back-end (like a post preview) so you shouldn't even toss in a redirect for ?p to go anywhere else.
At best, by limiting revisions saved, you can throw things off a little, and maybe by using a shortlink generator you can throw it off more, but complete disabling won't work. This will be true of most (if not all) CMS tools.