What an utterly bizarre hobby.
A notable one being related to the MMO Final Fantasy XI, with the "Maat's cap" item being created by Square Enix to praise a player who achieved the maximal level on every job available in the game. Which back then needed hundreds of days of slow and frustrating grind.
He says he saves multiple times (he mentions that he usually does it "at least three times") which I thought would mean that he uses multiple different saves but instead he seems to only have one single save that he overwrites multiple times. So in the end he just increases the wear of the underlying flash and has no backup. Not to mention that it increases the change of having a save being interrupted in case of power failure. That's bold.
Frankly the fact that he doesn't appear to have even a single backup save on what appears to be an otherwise empty memory card makes me question the authenticity of that whole ordeal. On the other hand I guess I shouldn't presume to understand the mindset of somebody who's willing to go through something like this.
I liked that thought.
Yes if you want to be reductionist and just call this 'playing a game' then no, 'playing a game' isn't a strange hobby. But that's like calling BASE jumping, 'just jumping in the air.'
The only notable here is that the game is seemingly repetitive, but even there each level is different and requires a new way to hit the ball.
People have played Counter Strike on de_dust2 (a specific map) for almost two decades as this point. They play the same map over and over again, is it repetitive? Maybe, but each time there are new people so it makes it a new challenge each time.
People have played solitaire for their whole lives, again the dynamic comes on each "level" (i.e. new shuffle).
I am 100% sure that the play time of these people dwarfs this guys play time many many many times over.