Lightroom :: Why File Creation Date Changed (Mac OS)

I'm finding that Lightroom changes the file creation date when embedding metadata. I notice that this behaviour differs from Bridge, which manages to write metadata changes to the file without affecting the creation date, only touching the modified date.
 
I've read in other threads that it doesn't matter anyway because moving files between disks will write a new file and therefore a new creation date, but while this may be true in some systems (I don’t know) this is certainly not the case with Mac OS. For example, I have files going back to at least 1998 which have been moved from disk to disk to disk yet still retain their original creation date. Which is as it should be. For many of my older images there seems to be no recognisable embedded capture date anyway, so the file creation date is the only time stamp.
 
It seems perfectly logical that the modified date of a file should be updated to reflect that the file has been modified (e.g. though adding metadata), but it seems equally logical that the file creation date should be retained as the original date that file was created. Changing them both to the same date seems to be a needless loss of information.
 
Some might argue that the process of adding metadata to a file creates a new file, therefore the creation date needs to be updated to reflect that. But I would say that the creation date should be what a normal user would understand as the creation date. We don't expect the creation date to be changed simply because a file is rewritten to disk (for instance when defragging), however technically accurate it might be to say that it is a newly created file. And the difference in behaviour between Bridge and Lightroom shows that there is some confusion about this.