That said, I keep a clean engine too. I clean the throttle body out every time I clean the KnN filter. So about every 15000 miles I wipe out all that buildup. I think it comes from the PCV valve sending dirty air into the intake. That buildup is normal, but it does need to be cleaned. It will make the throttle stick at startup, and may not fully close, or otherwise not move correctly at startup. Once the top of the motor warms up the throttle moves freely. Not sure if that's directly related to your situation but I'd always suggest starting there if you haven't.
That's not a warranty fix, so you'll be charged for a TB cleanout and they may offer an Induction cleanout service separate to that. It's not a bad thing, I just think they charge too much since I know how to clean the TB myself and I also run seafoam in the gas tank very often, usually after 5-6 full tanks i put in 20 oz of seafoam and run the tank to fumes before filling up again. I actually get the big can, think it's a gallon container, it's much cheaper then the 16 Oz bottles even if those things are on sale. Point being, I'm probably as much as 80-85% cleaner then an engine they would normally get in to do the induction cleanout, so the stuff they do for like $100 wouldn't really increase my performance much at all. Because even they can't get me to 100% cleanout, they would just get me a little closer.