Yes, it is a choice and a right of freedom to choose.
I did not openly campaign for either "Yes" or "No" because I belong to the Fourth Estate. But I emphasized in my profile photo in Facebook that I was for "Yes."
Let us understand that we are given the choice as a right to take side on the issue. It just happens that sometimes choice is influenced by outside factors stronger than reason.
However, there are those who voted "No" not because they were influenced by outside factor but because that is their sincere rational belief that not to join the BARMM is good for them. It could be an opinion resulting out of what they had learned from and been informed on the information disseminated to them by the pro-BOL that might not have convinced them. Or, pehaps, not.
As a journalist, having covered many of the forums the pro-BOL had conducted to inform the public on the BOL advantages, I couldn't rely on the information they were feeding about the advantages or how good to be included in the BARMM. It is as if they were just simply saying "Believe me, this is good for all" without explaining the details why it is supposed to be good.
So, if they didn't vote "No," don't call them non-Muslim. 
:-)
:-)