Exotics aren't limited to raids though (with 2 exceptions that xur doesn't sell), there are raid specific weapons and armor as well as IB specific weapons and armor. And vangaurd and crucible, just by doing it means you have a chance to get something specific to that activity. Most raid weapons are better than exotics anyway simply because of the primaries with any kind of damage. That stuff is earned/awarded after you do the required activity to get it. The only earned exotics would be the ones from bounties because you know what you'll get in the end. I know that went to the left a bit but the point is, xur doesn't sell all the best gear in the game, his purpose is to sell armor and weapons, a helping hand to some or grimoire machine for others. If he sold raid specific stuff then by all means get mad, but til that day its nothing to get worked up over.