Why are most live albums also compilations?

Most of the (rock) live albums I have are also tagged by Roon as compilations. Ok, I guess some of them are a collection of live tracks from various concerts, but some, like Jimi Plays Monterey, are all from a single live performance. These exact performances don’t exist on other albums as a “greatest hits” (even though the songs in general do), but they’re unique to the live album.

If rock live albums are compilations, then basically every classical concert also counts as such, but none of them are marked that way.

What justifies the “compilation” tag? Can we fix this overlap?