Glory
The golfer you're working for will inevitably soak up most of that sports hero glory, but that doesn't mean you're left totally out in the cold. You know that feeling you get as a sports fan when your team makes a great play or wins a game? Working as a caddie can be exactly like that...but instead of yelling advice at people on the screen, you get to actually say it to the athlete involved.
Instead of high-fiving your friend after a brilliant win, you get to high-five the person who actually won the game. If you love golf, that's got to feel good.