My theory is that these people are mostly getting drawn in to technical details, and by diving deep into such details they lose sight of the overall image. A photographer who likes cameras but not photographs is especially prone to this.
How can you avoid being one of those guys? How can you train yourself to see the picture instead of a rectangular array of technical trivia? I'm going to take a crack at devising some exercises which might help you train yourself. The goal of these exercises if to create a little mental distance between you and a photograph, and to try to make it easier to see the image holistically, as a single complete thing in and of itself.
Find a picture, ideally something you like. Look at it for at least one minute, trying to memorize it. Look at details, patterns, textures, contrasts, whatever elements you think will help you remember the image. Now go away for a couple of minutes. Listen to some music, do some pushups, read a magazine. Take at least 2 or 3 minutes away, maybe more, until you're fully immersed in something else.
Now close your eyes and try to reconstruct the picture in your mind's eye. Paint in, in your imagination, as much detail as you can remember. Contemplate that imagined picture for a while, and then open your eyes and go look at the original some more.
Step back from the photograph. Stretch your arm out full length in front of you, and hold out your hand. When the photograph is about the same size as your hand, stop. Look at it. You're physically quite far away, details should be obscure. You can apprehend the image as a single thing, without really moving your eyeballs. Pause. Look at the image and think about the image, think about what it is a picture of.
Look at the photograph from varying distances, but always far enough away to obscure technical details to a degree. Sharpness, exact focus, and so on. The overall color palette and contrast treatment will still be visible, but try at any rate to put physical distance between yourself and the image. What do you notice about the image at one distance? What about when you step back 3-4 feet further?
Look at the photograph under very dim light. Things like contrast and color balance should be hard to see now, and perhaps you can ignore them more easily. What do you see now?
Again, the goal is to hide technical detail, and to force you to look at the image as an image. Does it work? Again, think of it as a picture of something and not a technical exercise in photography and post processing.
Exercises #4 through infinity
Invent any new physical process for looking at pictures. Blink rapidly, use peripheral vision, put your nose against it, and so on. Anything you do differently has a chance of breaking you out of the process of looking at the image as a collection of degree-of-contrast, sharpness, white balance, and other technical features.
When you're looking at your own work, whether a photograph you have taken, or a photograph you are "working on" in some photo editor, ask yourself always "does this look natural?" or "does this look right?" Don't ask questions about contrast or sharpness of color balance. Ask if it looks right. To be sure, when you're adjusting contrast, you should be asking yourself if the contrast is right. But then, step back and ask if the picture itself is also right.