What happened to fun for fun's sake?

[Fortune_Cookie]

But even though I understand that some people consider it fun to speedgrind to max gear, the issue still remains that, ultimately, the end goal for many of these people is to quit. They just don't seem to realize that that is their true end goal.

Different people are different. Optimising a process, such as a dungeon run or the acquisition of BiS, in and of itself is fun for some. They are playing the game in a way that offers entertainment to them, just as you are. That doesn't mean their end goal is to quit. That may be a consequence, but not necessarily their goal. Their goal is to play efficiently, which equates to fun (for some). The consequence of reading a book is that at some point you run out of pages; doesn't mean you can't enjoy the process of getting there.