"I think women should be barefoot and pregnant" is a factual statement about Charlie's preferences which are themselves reducible to the physical locations of atoms in the universe (specifically Charlie's brain). Futhermore, the statement "We should make sure women remain barefoot and pregnant" follows logically from Charlie's previous statement about his preferences regarding women. I would expect you to say that Charlie is factually wrong. In which way is he factually wrong and Bob isn't?

Charlie is, presumably, factually correct in that he thinks that he holds that view. However, while preferences regarding colour are well established, I am sceptical regarding the claim that this is an actual terminal preference that Charlie holds. It is possible that he finds pregnant barefeeted women attractive, in which case his statement gives valid information regarding his preferences which might be taken into account by others: In this case it is meaningful. Alternatively, if he were raised to think that this is a belief one ought to hold then the statement is merely signalling politics and is therefore of an entirely different nature.

"I like blue and want the town to be painted blue" gives factual info regarding the universe. "Women ought to be pregnant because my church says so!" does not have the primary goal of providing info, it has the goal of pushing politics.

Imagine a person holding a gun to your head and saying "You should give me your money". Regardless of his use of the word "should", he is making an implicit logical argument:
1) Giving me your money reduces your chances of getting shot by me
2) You presumably do not want to get shot
3) Therefore, you should give me your money

If you respond to the man by saying that morality is relative, you are rather missing the point.

The statement "We should paint all the buildings in town blue!" is not a claim in need of evidence. It is a command, an expression of what Bob thinks should happen. It has nothing to do with how many people think the same.

I think you are missing the subtle hidden meanings of everyday discourse. Imagine Bob saying that the town should be painted blue. Then, someone else comes with arguments for why the town should not be painted Blue. Bob eventually agrees. "You are right", he says, "that was a dumb suggestion". The fact that exchanges like this happen all the time shows that Bob's statement is not just a meaningless expression, but rather a proposal relying on implicit arguments and claims. Specifically, it relies on enough people in the village sharing his preference for blue houses that the notion will be taken seriously. If Bob did not think this to be the case, he probably would not have said what he did.