Well, if someone is after tailgates, I would image locking it will hardly slow them down. Consider they need to disconnect the harness. I would guess once done, plug in a handheld power supply to unlock. Or, since there's a good bit of room between the tailgate and bed, a tool could be inserted to trip the bolts. The tailgate bearing lock adds another step that should be more difficult to defeat.You're missing a needless piece of hardware?
Seriously, nothing. It's peace of mind for paranoid folks.
On the other hand, the chances of a specific tailgate being stolen is pretty low.