Disagreement and Hypocrisy are two things that every society has, and if you want yours to be realistic you have to include them too.

You would be hard pressed to find any society that all agrees on something. No matter how clear or obvious there are some people who will disagree. For religion this means there will always be disbelievers. For science this means that there will be people who doubt the most established scientific facts and theories. There are people today who believe that the earth is flat after all. No matter how obvious or widespread an idea is there will be some who disagree. Now they may not do so in public but such people will exist.

The second is hypocrisy, and I am not talking about individuals, although they do exist. I mean that a society will be about one thing and it will in some cases allow or encourage the suppression of that one thing.

Not to say it won’t happen for a reason, maybe even a good one. For example if a planet all follow one religion. The highest law might say that you must be a member of the church and must follow it. I would not be surprised if there was a place where unbelievers would get together, at least semi openly. Even if officially it was never allowed the people in charge might be wise enough to know that some valve was needed.