Why is the DVD physical setup so weird?

I was trying to watch a netflix DVD with Plex but it was either scratched, defective or pressed wrong. I tried to play it by selecting the individual files on the disk, but finally gave up without much luck. Just sent it back for a replacement. But, while trying to make it work, I looked over the makeup of the physical DVD.

This was an old series with eight half-hour episodes on a platter. But rather than what you might expect, of having the warnings, the menus, the coming soon previews and then the eight shows, the actual content was set up like the following...

Episode 1
Episode 1
Episode 2
Episode 3
Episode 3
Episode 3
Episode 4
Episode 4
Episode 5
Episode 6
Episode 6
Episode 6
Episode 7
Episode 7
Episode 8


In other words, there were multiple copies of some of the files - and they couldn't be different angle views. This series is way too ancient and all the file sizes are exact for that episode.

Why do this? By using the space for the useless (I assume) copies, they could get twice as many episodes per disk. Or, even more also-available-on-DVD clips. And how does a player know which one to use?

Just wondering about the weird setup. Any video experts out there?

I doubt those were copies of the same files. You really need to know the extensions of the files to be sure though.