He does? Outside of the box he offers little. He's hardly been prolific since he joined Chelsea either.
Just because Giroud has had a few average games recently, it doesn't make a player who did well at a smaller club better than him based on highlights. Giroud generally defends well for the team in addition to his link play (see him setting up Ramsey today).
We could better than Giroud of course, but that certainly wouldn't be Ba.