I just read an intriguing article by Russell Smith, writing for The Globe and Mail. In “You say KILLameeter, I say kil-OM-ater,” Smith suggests that “Anger over pronunciations usually hides a deeper anger at something else: the creeping influence of a culture or a class. It very much worries people when a common vulgarism or lower-class pronunciation becomes the accepted one.”
He may be right about this, as well as in his belief about the inevitability of the triumph of popular pronunciation due to the fact that “people with educations in language are far outnumbered by people without.” His pragmatic conclusion is that enforced pronunciation of kilometer is unlikely to further the cause of clear communication, so he declines to join the cause.
I understand the pragmatic point of view, but as a logophile, I also understand the distress over inconsistency and a loss of parallelism. Precision, like innocence, once abandoned is gone forever.