Is throttle body cleaning needed at 30,000 miles?

Not in my experience. Some driving conditions and/or designs , lead to carbon/sludge build-up quicker than others , but 30K is pretty early , especially on a newer(2013) model. I would question the advisor and ask to see why they are recommending it. IF he balks at that , call B.S. and politely decline. It is there JOB to try to make a profit , but there is enough legit stuff out there. Maybe by 60K , it'll be a worthwhile recommendation , and do it then.