Why would you wonder that ?

I've heard of people going off the deep end. Happily, I did not throw the baby out with the bathwater. When I discovered that the Bible was mythology rather than reality, I discarded my religious beliefs. However, I held onto the ethics I had learned from the Bible, based on neighborly love. I had to find a new basis for ethics, not the fear of a vengeful god, but my own happiness. I am happiest when I love my neighbors, practice kindness, and do good deeds that make others happy. Because I had to re-examine my ethical foundation, I became more ethical as an atheist than I ever was as a theist.

If they were to suddenly lose that belief, they would also suddenly change who they are so perhaps their sudden lack of dependency on their invisible sky-daddy would allow them to become aware that they are a part of a social fabric with consequences for actions taken against society.

There are probably a few that would resort to an anti-social behavior but the real world outcome of this thought exercise is so unlikely I'm not going to worry about such an event.

It didn't happen in my case.

yep religion is a crutch to thinking. It is hard to take full responsibility of ones own actions and understand how it affects the ones around. In religion, if you make a mistake, you know you will be forgiven because it's ultimately never your fault since it's gawd's plan. Just look at all the catholic church scandals being exposed. Each of those child molesters have asked and been given forgiveness. That loophole and that book will never be conducive to ethical behaviour. It's cognitive dissonance.
(nice new profile pic by the way)

Personally, I think the 'Faithfools', should they ALL suddenly shed their beliefs, would, for the most part, would firstly act like they are in total denial, then slip into the same/similar mindset as exhibited by cage breed birds who have suddenly become free range, i.e. they would mill around dazed, confused, unsure of both themselves and their surrounding, their minds in a dazed, misty fog, stumbling through hours,days, weeks, even months almost aimlessly since their supposed ' guiding light' in life has become nothingness and meaningless.
That is why I refer to them often as being SHEEPLE, since I have often observed actual sheep suddenly deprived of their flock leader/s and those are their actions to a 't'.

I actually don't think most of them would devolve into monsters. I was mildly surprised that I didn't when I deconverted, but there was no basis other than operant conditioning for me to think that I might.

If anything I feel I am more genuinely moral after my deconversion because there is no element of fear or meeting expectations or demands; doing the right thing is now 100% voluntary and chosen. I don't treat people with kindness for example because some sky wizard or pastor would be disappointed in me or angry with me if I didn't; I do it because I choose to and like contributing to civil society and the happiness of others.

You forgot the "eating babies" bit.

I've always thought Santa is just a metaphor for GAWD. How to control the kids? Santa! How to control the adults? Jeebus! "Cause everyone knows we can't manage our own ethics!