Many, for different reasons.

The most specific example is Skyrim.

XBox 360 : Original, Legendary
XBox 1 : Special Edition
Playstation 4 : Special Edition
PC : Legendary, Special Edition

Why? Originally, something close to love for the world they (Bethesda) created. After the 360, it was to try modded versions. When I discovered the limited scope of mods on both consoles, on to PC.

Because I also owned Morrowind, Oblivion, Fallout 3, and New Vegas, and liked them for mostly the same reasons, (immersion, verisimilitude), for a long time just seeing the Bethesda name was an instant buy.

But I Ain't Like That Now.

Different consoles would be a main reason, as listed.

I'd bought several copies of Ring Runner though, mostly for trades and giveaway to friends. But this was a while back. Looking back i have 2 copies left. Yes Ring Runner is that good, at least if you like neutonian physics and fighting in space that feels like Inner Space.

why buy consoles when you have a pc?

Funny story, i was gifted Skyrim back in 2014 i think, and my computer couldn't handle it...

Also funny story, in 2017 when i moved, i only had my laptop available with me, so i got a PS3 second hand with Skyrim included... It wasn't until a year later i moved all my other stuff and later before i build a system from scratch as my newer gaming rig.

Curiously i hadn't given Skyrim a real chance until after 2017, mostly due to changes in mechanics and raising the dead caused them to turn to ash so raising someone to carry your extra crap didn't work very long... Course mods and other things fix that.

I re-purchased some older games I had on physical media to get a drm-free digital copy.

I bought some games I really liked to my friends on their birthdays (less so now, but for a couple of years, I did it regularly).

That's about it.

Usually games that are a blast to play

Batman Arkham Knight
Battlefield 1942
Bioshock
Call of Juarez
Indiana Jones Fate of Atlantis
Flatout 1 & 2
HOMM 3
Morrowwind
Just Cause 2
Oblivion
Painkiller
Prey
Sacred 2
Saint Row The Third
World of goo
World in conflict

And of course digital download of classics like Settlers 2 , C&C , ...

yeah that seems a viable usage , but do you use console if you have a proper pc ?

Mount and Blade, including Warband.

Hmmm... It was workable for the most part on Console, for a while at least. Once the save gets to a certain point it isn't reliable, so it's better as a Demo system and if you want to play totally Vanilla for a while.

I bought Fallout 3 three times (German cut version, English uncut and the Gog version). Also Oblivion and Morrowind, three times each. Man, Bethesda got a lot of money from me.

So many games bought twice. I bought them since I wanted the easy to store digital versions. =P

Fallout 1 & 2 (retail and now GOG)
Fallout 3 (retail and now GOG GOTY)
Dragon Age: Origins + Awakening (retail and now GOG Ultimate Ed.)
Drakensang + River of Time (retail and now GOG, just base, no RoT) =(

and quite a few more that I can't think of the top of my head.
.

I find it rare that I even play game twice. Fallout 4 I did two times. I plan to play Cyberpunk again too at Expansion.

I went crazy at ESO though. Leveled up all Classes. I could play Doom Eternal again for sure.

Mount & Blade: Warband.

Civilization I-IV