I suspect in SGI's case it was probably mostly another demo to show off their graphics capabilities. Nobody
used it, but everyone I know who tried out the SGI boxes at uni had their five minutes of fun with it.
Things like that and running xearth as the background when logging in on the Indy's made them stand out massively next to the Sun boxes with monochrome terminals in our computer labs, which seemed ancient and outdated.
Heck, even booting them, with their nice blue gradient background and metallic frame around the window where the boot messages scrolled by set them apart from the boring Sun boxes. SGI early on had a lot of the design sense and flair that Apple has today.