You'll probably deal with ideas like this in the next article, but in certain circumstances, I love grinding. I get this feeling on older games, ones that I am very familiar with. There's a Zen-like peace that comes from running back and forth in a single area, killing the same monsters in the same way. It's not entirely the reason I play games, but it's a kind of meditative repetition that gets me very relaxed and takes away stress.
Example: dusting off my old SNES and popping in The Secret of Mana, I know I'll need to do a lot of grinding, running back and forth between Pandora and Gaia's Navel in order to get enough XP to max out each weapon for each player. I enjoy advancing the story, but in between those events I will, sometimes for hours, grind for the pleasure of it all. My muscle memory still knows that game, and I can perform the kills almost without thinking. This sounds boring, and, in truth it's not terribly exciting, but it gives me a transcendent feeling that prayer beads or chanting must give to others.
Psychologists talk about "flow state," athletes talk about "the zone," and religious folks meditate, and my gaming experience with grinding is similar to all of these: my reflexes and reactions become automatic, leaving my higher awareness free to work things out or just rest.
I don't think you could sell a game on these ideas, but they're part of games, I think for a lot of people. How else could games that involve so much repetition feel neither boring nor exciting, but still generally good enough for people to continue spending so much time and money on them?
Then again, these might just be excuses to keep me playing Secret of Mana...