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.
(..) let all the boys see my underpants. You can't blame yourself. When your prefrontal cortex fails to make you happy, promiscuity rewards you with the needed flood of dopamine. We neurobiologists refer to this as the "skank reflex." You know what? Let's get out of here. (..)2011 TvShow: The Big Bang Theory Title: The Skank Reflex Analysis Season: 5 Episode 1