Language confusion

I just read a current PCV blog "Eleven Degrees North" by Philippines volunteer Ryan Murphy who is living near where I was stationed there. This is a comment that I wrote in response to his post yesterday:

In training (RP-Group 39) I was in the Cebuano language group. Ron was another volunteer in our group. Then he was assigned to a town near SanCarlos in Negros. Now, San Carlos was on the edge of the Cebuano/Ilonggo divide. They are related languages so it usually didn't cause any problems but one day he was ordering lunch or something and when he was asked when he wanted his meal he said, "karon". So the waitress was Ilonggo and didn't bring it. So he then said, "karon dayon". (dayon just emphasized the "now" that Ron was saying.) She still didn't bring the meal. Eventually, the misunderstanding was cleared up and Ron did get his meal. I wonder how these two related languages came up with such opposite meanings for the same word?