Ha! I think that he thought you meant to say "Take that Roger Waters" instead of "Take that Roger haters." But since you were complimenting Roger Waters, it wouldn't make sense to say "take that Roger Waters." --Unless the bass line in Echoes was one of the Pink Floyd bass lines that was actually played by David Gilmour. In that case, "take that Roger Waters" would have been appropriate.
Oh. I see. And you are correct, I am a huge Roger Waters fan, and whatever basslines Gilmour may have played, Echoes is certainly one of Roger's own. He doesn't play very fancy but he has a distinctive style.