What I don't understand is that, when I view a canon RAW image in my Mac preview will display the image as I shot it in camera, but when imported to Lightroom it initially displays in the in-camera settings, and then once finished loading/rendering, it changes and loses all the original stuff... So why can't it keep it, since it obviously is able to read and display the info.
It's not displaying initially the in-camera settings, or not directly. It's displaying the small embedded jpeg preview that's stored inside a raw. That preview has been made with the in-camera settings, so indirectly that's what you're seeing.
When you shoot raw, a small low-res jpeg is stored in it as well, for things like the in-camera preview. When you display a raw image on the back of your camera, you're not seeing the raw, you're seeing this little jpeg.
Lightroom initially displays this preview also while it's building its own preview from the raw. Once it has its own preview, it displays that, as it accurately reflects Lightroom's raw rendering (which the embedded preview won't).
We were discussing this a few posts above. John Beardsworth explained that in Aperture, you can see this embedded jpeg later, if you want. I think that would be a neat feature in LR, too, but John says it comes with a health warning in Aperture, as it's NOT a preview of the LR rendering.