While I don't typically condone gold buying, I can 100% see why someone would do it in today's world.
15 years ago, most of us were younger with a lot more free time. While I myself most likely will not buy gold, I can see why someone would.
The hours of farming that used to be worth while back then can seem like a pointless thing now.
I can almost guarantee that all of us while farming in vanilla at some point said, "Damn, I wish I didn't have to do this and just had the gold."
Buying gold was a lot harder and more..."Sketchy" back then as well.
Knowing you can "Skip" hours of killing the same mob over and over and over and over for hours does have a nice appeal.
Also, no, I personally don't think having to farm mobs for hours makes for a good thing. I felt the same when I had to do it in vanilla.