It is highly unlikely that the carbon has built up in that short period of time. In my experience the effects of an induction clean is only felt when the vehicle has never had a cleaning and the mileage is above 100k. Put a can of bg44k in with a full tank of fuel.
Put your hand on your wallet ( or purse) and run, run, run! At 28,000 miles you shouldn’r need it. And you might want to find another place to get your vehicle serviced W;)
Yes I’m with the group on this one as this would be the classic “upsell”. However when the time does come and you feel you need to clean the top end of the engine I preferr to use that type of service over poring something in your tank to do the job. The stuff you pour in your tank is just not as effective. You might think about that type of service around 60-80K but not 28K.
Guys, thanks for the help and advice. I really can’t say thank you enough. @twiggy I will try talking to the manager and what not but since it was a dealer, I seriously doubt that they will care much less do anything.