Did religions start as a Facebook of the ancient eras, for people to socialize, have fun and frolic?

That is a very good analogy. However religion is more than a "social network." It involves a system of beliefs, values and morals a group may share. I suppose since we`re using the "Facebook" analogy why not use the groups on fb. One group on fb represents one religion (along with the beliefs, morals and values). Facebook can represent a larger population like the world or a city. As they`re very different religions in the world as they`re very different groups on fb you can see how religion can connect people together like a social network. People in general are all connected, just like the groups are on fb. So in a way you can say religion is a kind of ancient fb, however it only pertains to the different groups because not everyone practices the same religion nor have the same values. Hope it helps.