I most certainly could be wrong, as I'm not familiar with much of popular music; however, my main point really is that when beginning an understanding of music theory, after focusing on your major, minor, and perhaps, pentatonic scales, it is far more important, in my mind, to begin an analysis of harmonic function, and harmony in general, then it is to begin some desire to learn modes. While you would never want to limit your musical vocabulary, in any genre, it's putting the cart before the horse in my mind, as how do you know how to apply locrian, when you still don't understand harmony?