I would say that values that may not be utility maximizing on the individual level, but which are on the cultural or national or even species level so long as most people hold those values, are totally rational. It's like chosing cooperate in the prisoner's dillema but with billions of players; so long as most of us choose cooperate we are all better off. So in that situation it's rational to cooperate, to encourage others to cooperate, and to signal that you cooperate and reward others who do.

"The civic virtue of voting and taking your vote seriously" is a great example of a virtue like that. It doesn't directly matter to you if you do, but we all are much better off if most people do.