Why do big new Blu Ray releases always come with a DVD?

So I saw that Wonder Woman is up for preorder on Amazon and lo and behold one of my most annoying pet peeves is still around.

WHY THE HELL IS THERE STILL DVDS WITH BLU RAY RELEASES?

I understand why there is a code for a digital copy. That makes sense with tablets and smartphones. But, blu rays have been around for over a decade now and a blu ray player isn't that expensive. It would be like Sony releasing the PS5 with composit connectors.

It wouldn't bother me if was still the case, but I could still just get the blu ray by itself. But there is not other option other than getting the new combo packs that come with a blu ray, 4k blu ray and digital copy. Even if I was only saving $5 to just get the blu ray, I would prefer that.

To give to your friends who don't have Blu-ray? So you can have a back up of the movie in case something happens to the Blu-ray?

I don't buy Blu Rays so i can't see the problem.

So they can charge you more