I am normally always interested in a language for academic reasons ( = the language itself) and not in the culture, or visiting there or anything similar. I often have very little interest in the country of the language I'm learning.
Any attempts to insert "Did you know....?" about the culture of a country into a learning text is going to annoy me. I'm not interested in what people in country X eat for dinner, I'm interested in the pluperfect tense of that language! With some languages, it's unavoidable. Chinese for example. You need to know some Chinese customs to make sense of some words/phrases. If it helps with understanding the mentality of the language -- I'm all for it.
But if it's just "People in Spain traditionally eat 12 grapes at midnight on New Year's Eve"...that's not a helpful fact for learning the language and I'd rather it stayed put in travel guides and culture essays where it belongs. (I'm aware this is a minority opinion! )
Therefore, knowing about their culture might help you a lot to speak their languages.
In my point of view, learning a new language is a holistic process and all sources of information (when valid and reliable, surely) are valid to support you. Some people are more familiar with some ways of learning, others feel more confortable with other methods, but in general I believe that you have to find the strategy that better fits you. Obviously, there are some kind of "culture" that does not contribute that much when you are learning a language, that's the reason you always have to filter and only use the best you have.
In my case, I like to understand a culture and see how people interact, how they see the world, how is the accent, how they use language as an expression... if I'm able to visit this culture, for me is the ideal and helps a lot.
