One of my first DVD experiences was the original Blade film, and it had an alternate ending available to play.

That blew my mind and was an awesome experience. In the age of dial-up internet it wasn't like you could find and / or watch that online.

Yeah, early on in the DVD era having deleted scenes and commentary tracks was totally new and a big deal for a lot of us.

In the peak of the DVD era my SO and I were both big movie fans, and at one point had watched literally everything the Blockbuster and Hollywood video in our neighborhood had. There just wasn't the embarrassment of riches of the post youtube world.

DVD supports an absolute amazing amount of features many of which were rarely if ever used, and some never implemented on most players, likely.