No one has really said that to me. I'm not one of those no-life kids who's addicted to Pokemon. I usually only play it randomly, like when I'm incredibly bored on a long car drive, or on an airplane. And I have about two friends, and a second cousin, who just like me, barely play Pokemon. I really don't play video games that much. But when I do, it's usually something random and not Pokemon. I have many games, but I don't like Pokemon specifically. I play basically anything and everything, from Mario to COD, so I so don't really devote any 'extra' time to Pokemon, besides going to this site. But half the time I come here its just to talk to my friends or to see what people are whining about on the XY forum. I don't even like the cards, or the anime, or the manga, not even competitive battling. I play the game only for a 3 week period after getting it, and really never play again til the next game comes out. I'm basically a casual gamer, not a specific Pokéfan.
But if someone did say that to me, I would say "Go suck some Pokéballs". Then walk off in badass slow motion, maybe stick up the finger, leaving the person behind me stunned. <3. Unless it was my mom or dad, then I'd be like "Oh, um... its fun to play... and I like it...".