Language class is inherently a cultural education class so I think it is perfectly natural for cultural education to be included in foreign language class. I don't know how one could effectively learn a language without learning something of the culture in which the language is spoken. Cultural education would enhance language education class.
Just knowing a language is not enough. One must actually become immersed in the culture of another civilization to truly understand the language and how it is used and how to use it in context with a member of this culture. Cultural education is vital for people to properly approach new situations in context.
After having worked in a multicultural, bilingual elementary school. It's easy for me to see how cultural education, combined with language classes, is the most effective way of giving the kids the most complete education. When you combine the two, it becomes much easier to absorb the language. It creates a new level of relevance and understanding for the learner.
I do not believe cultural education should be included in foreign language classes. Learning a foreign language is difficult enough without trying to cover the culture that uses the language. It's not that I don't find the information valuable, I just don't think it is the time or place to address the topic.