You know, I was at 1800 Tommy Points when we lost to the Lakers and to tell the truth, the more I had, the less they meant (or so it felt). I remember when I got my first Tommy Point around three years ago, it meant the world to me (well, maybe not, but it was a really cool thing). I just feel it's a cool feature, even though it's not as cool as it used to be.
You're right, there's definitely a law of diminishing returns with these things.
Random story (nothing to do with your post, ACF): Back in the very old days, when TPs first began, there was another poster (he no longer posts here) who actually argued he was a worthier poster than others because he had more TPs than me. He and I were neck-and-neck for the TP lead for awhile (we're talking like 50 overall here), and I kept noticing that my TPs were staying level, or even declining. Fast forward in time until fairly recently, and I was able to see that I was given dozens of negative TPs back then. I bet, 10 to 1, that it was that poster, trying to keep my total down so he could "beat" me.
The minority of people just take these things too seriously. Like Redz said, they're just meant as an attaboy, and as a way of making others feel good. They're not a thing to be hoarded or collected, and certainly not something that people should fight or cheat over.