Of course it is. You buy them from Xur? You busted your ass for the coins so yeah you earned the hell out of it. Yeah coins are easy to get if you have 3 characters and unlimited gaming time but not everyone is so lucky. You worked towards a specific goal and you did specific things to get there. You got it as a drop? You didn't earn shit. You happened to get something awesome by sheer luck of the draw while doing something you were gonna do anyway. The only way to EARN gear in the game is through Marks, Exotic Bounties and Xur. Thats it. Beyond that its nothing but pure dumb luck of the draw.