It's been like this since at least the 80's OP. I remember opening a copy of MS Flight Sim and they put the floppy disk in the user agreement, opening the folder the disk was in meant you agreed to the terms. One of those terms specifically said you didn't own the software (understood this even as a kid).
It's mainly to keep people from copying the software and then trying to sell it, claiming they bought it so it is theirs to distribute how they wish. It's basically saying the coding/programming is owned by the company and you only get the rights to use that copy of it.
No, you still own the disc and everything on it. (Unless you're in the US where those EULAS are probably legally valid, even though i don't think the supreme court has said their piece yet).
What's stopping me from making a copy of the disc i own is copyright legislation, not the "i'm not selling copies, i'm selling licenses" eulas. That shit is not valid.
So i can start selling copies of the disc i own in about 2000 years when the copyright has finally run out and no more extensions has been given.