Hank Schulman tweeted this in response to the notion that spring training stats determine playing time.
If Hank speaks for the organization (likely, he is familiar with their thought processes -- at least, more than we are), then his tweeted reply has some internal logic to it.
The Giants sign free agents or re-sign vets every year and think, "This is our starting lineup." They go into every spring training with such certainty. They might claim competitions, but they're always talking about the backups. Now here's Burriss with the chance to start because the guy they penciled in to start the season (Freddy Sanchez) went down with injury.
Now they have to choose between backups: Theriot, Fontenot, or Burriss. Well, Burriss is having the great spring and gives the team switch-hittyness and speed and he's a prospect they've been high on, so he's winning the battle of the backup-turned-starter.
We don't have to like it or agree with it, but at least there's some reasoning behind the decisions.