What exactly is a "bootleg sampler"?

When I got my Sega Saturn video game console in 1996, it came with a "demo disc" similar to the PlayStation’s iconic "Demo 1" disc with its fancy menu system and music and everything.

However, they used a very different "branding" for the selection screen and disc artwork for the Saturn. It says "bootleg sampler" and looks like this: https://youtu.be/NGEw0h6y_m8?t=3

What is a "bootleg sampler"? I know a "bootleg" is like an unauthorized recording of a live music performance for profit, or something. It appears to also have other, similar meanings.

But what is a "bootleg sampler"? Why do they call their own, very authorized playable and pre-recorded demos "bootlegs"? And what is a "sampler"? Bootleg sampler? My head spins from trying to understand this. I’ve been wondering about this since that day in 1996 when I finally got my Saturn after Sega heavily slashed its price.