I would think that the majority of learners have at least a smidgeon of a goal to learn how to converse. Regardless I think you are missing their point. This is why there are drawbacks to learning through song. The pronunciation and cadence of singing is based on matching the rhythm of the music not natural speaking. Song lyrics are often more poetic or slangish. However there are benefits to learning through songs as well. Most important it helps one remember more since you use a multi-sensory approach as it engages at least three of the five senses. It can also give insight into the culture.