Being exposed to a song does not really counts as learning, but another thing is an analysis of chords, lyrics, post-procession effects, rhythm. Intention to repeat that in their own creative project is a judge.
Yes you have. But that has happened by accident. You didn't try to learn the song, you just happened to be somewhere it was playing many times. (I say 'many' if you really learned the whole song correctly)
If you really WANT to learn something you cannot rely on such accidents happening. Accidents are not a method.
In some genres, such as opera or modern pop songs like "pumped up kicks" or rap with some well-hidden links, or just a song containing some foreign language - this approach is so hard that if you want to learn you just download the lyrics and just read with no distortion of sense.
