what is a BG induction service on a 2009 Toyota Scion on 2009 Scion xB

service center said it costs 149.99. Is it necessary

Asked by for the 2009 Scion xB
It's necessary ,for them to be more profitable.(MY OPINION).THAT SAID,? how well have you really maintained your car? Factory filters ,proper mileage intervals for service ,or do you wait for problems ? Know what I mean? a nice respectful way.