There wasn't anything in your previous post that indicated that you wished to learn anything. There was no introduction that you came from the Windows PC world. You didn't ask for any help with anything, you made a declaration, a statement. It was in the form of a rant. In a honey pot.
As to the reason that a user cannot merge Apple IDs or transfer content from one Apple ID to another, Apple owns very little of the content of the hundred's of thousands of apps available from the iTunes App Store; iLife, iWork and maybe a couple of others, everything else belongs to the developers. And Apple's agreement with them is like it's agreement with the other content owners of the music, movies, TV shows, books, etc., the content is licensed from the content owner to the Apple ID that was used to acquire the content (paid or free.)