The stuff being reported around Facebook is certainly cause for serious concern. "Cult"[0] has a pretty contentious meaning which is problematic when applied to Facebook without further analysis—it can certainly be separated from issues of loyalty and morality. "Cargo cult"[1] really doesn't apply at all, at least in the context of what you're describing here.

[0]: https://en.wikipedia.org/wiki/Cult

[1]: https://en.wikipedia.org/wiki/Cargo_cult#Metaphorical_uses_o...