Why would anyone want to cover prog and fusion? I might like prog more than I used to, but it's still not a very "coverable" genre.

My guess is that they like it.

Pretty much.

Just because hipsters decided it was "dead" doesn't make it so.
Like all genres there was a shitload of gawdawful crap and some good stuff

Alright, why would anyone ELSE want to LISTEN to prog and fusion covers?

I think the fall of Chula's band answers your question.

Ah, the world makes sense again.

My memory is foggy but at one time or another we played stuff like this.

Pat Travers - Life in London
UFO - Rock Bottom
Be Bop Deluxe - Axe Victim
David Bowie - Ziggy
Rush - Bastille Day
Jimi Hendrix - Let me Stand Next to your Fie
Robin Trower - Little Bit of Sympathy
Yes - Siberian Khatru
Rush - 2112 Live Version
Pink Floyd - Pigs
Lenny White - Stew Cabbage and Galactic Beans (look it up :-)
Zeppelin - The Song Remains the Same
Pat Travers - Gettin Better
Rush - La Villa Strangiato
Yes - I've Seen All Good People
Be Bop Deluxe - Third Floor Heaven
Zeppelin - Moby Dick
Rush - Xanadu
ZZ Top - Waiting on the Bus
Kansas - Carry On Wayward Son
Jeff Beck - Cause We've Ended as Lovers
Rush - Circumstances

And we sprinkled in a bunch of originals that were extremely Rush influenced.

Gay.

You'd have to live 5 lives to get as much as I was getting back then. :D