Why didn't Mercedes get a penalty for their dummy pitstop?

Max Verstappen and Romain Grosjean both got penalized for their actions at Monza during the Italian Grand Prix, but Mercedes, Sebastian Vettel and Lewis Hamilton were left without penalties for their actions.

Mercedes did what looked to be a dummy pitstop, which is why race leader Kimi Raikkonen came in shortly after. Officially, this is disallowed, as the FIA decided in 2013 that teams can't go out of their garage without a reason. However, Mercedes didn't get penalized for running out of the garage and preparing for a pitstop, only for Lewis Hamilton to stay out several laps more.

"We don't want teams to be in the pits if it isn't necessary, that's why we have the rule," F1 racing director Charlie Whiting told Motorsport-Total.

That's the official explanation, then.

Toto Wolff, team boss at Mercedes, also insisted that the dummy pitstop wasn't a smokescreen.

Should Mercedes have been punished for this? Leave a comment with your thoughts!