Sure. If it hasn't been created by the UI yet when your addon loads (which it might be - did you check?) then you can do it on PLAYER_LOGIN to make it only run your code once. That, or you can unregister the PLAYER_ENTERING_WORLD event after doing what you need to.
Your code could possibly be only 1 line.
That said, we are talking a negligible performance/footprint increase because the addon is so small and does so little anyway. I was just clearing up your misconception.