Benefits?
You don't have to pay porters and others to carry and store stuff for you. You are more able to take public transportation (like flight crews and airport personnel do from airports), rather than shuttles, and (often scam-prone) taxis. You can even walk. All of which also bring you into more intimate (hence rewarding) contact with the people and places that you have come to visit.
If there is a bottom line, it's that traveling light is simply a more stress-and-hassle-free way to go. You have more time, because packing takes little. You waste less energy hauling stuff. You know what you have, where everything is, and that it's sufficient. We've all seen those hapless folks at the airport, with too much baggage and anxious expressions, concerned that they have lost track of something, or left it behind.