"The roleplaying game and/or GMing approach I'm using doesn't allow for many opportunities for combat. If combat is primarily your preferred way of roleplaying, this game may not be the right fit for you." (Honest, accurate, polite.) OR "My game's more about roleplaying than combat." (Inaccurate, divisive, potentially insulting.) As for the issue of being "story-driven," all RPG's and all games are story-driven. Story is an artifact of play - it's created simply by playing. In the moment of play, it's a tale to be told. After the fact, it's a story. If you've done nothing but a three-room dungeon delve and never once spoke in your character's voice or contributed fictional descriptions to your actions, you've still told the story about 5 badasses kicking some orc butt in a dungeon. You've still roleplayed because you've made choices your character might also reasonably make given the context of that dungeon. It might, however, not be your preference as to how you told that story, which is perfectly valid. But you're still telling a story by playing. And, again, you're still roleplaying. Dice are just used to determine outcomes, depending on the system. Dice, complex mechanics, etc. is not indicative of the quality of the roleplaying that comes out by playing a given game.