Her success is 'just reward for' her hard work. [=she deserves her success because of her hard work]
She is 'reaping the rewards' of success. [=is getting all the good things that come with success]
The police are offering a 'reward for' information leading to the capture of the fugitive.
(..) for spending the day thinking of others instead of yourselves. Saturday. It was a Saturday. Now, a reward to the most selfless cleaner: A family vacation to the Grand Canyon. The winner: Ned Flanders. Surprise, surprise. (..)2016 TvShow: The Simpsons Title: Fland Canyon Season: 27 Episode 19