Depends on what they do.
Since these cars aren't direct injection, and gasoline is and of itself a very good solvent and has cleaning additives, I've never bothered with any sort of fuel cleaner as I view them as a waste. DI engines are a whole other issue.
If they are pulling off the Throttle Body, IAC, doing a full clean and reassembly with a new gasket, then that is definitely a good thing to have done. You can do this yourself. Plenty of online videos. Get some CRC Throttle Body cleaner and a Throttle Body gasket and it'll probably take you an hour or less.
Edit: Looks like these engines may have an electronic IAC...so no cleaning for that needed.
