Dani,
The airport authorities are not there to tell a pilot he needs to de-ice his aircraft. According to the author of this post, they asked the pilot, which is more than most controllers would even do. Most controllers have enough on their hands without having to worry about aircraft de-icing and MEL items.
Having flown for many years in that part of the world, I can clear up something. If a controller saw that the aircraft operated in a way which was reckless, he would have been forced to report such an occurrence to the FAA.
Everyone, please remember the most important part. We are talking about a highly experience crew who earns a very nice salary. I don’t question for one minute their decision to depart.
Iberia carries two crews on some long haul flights, thus the reason for having someone in the jump seat. Last time I checked, most companies do allow crew jump seats. At least 3 pilots made the decision to depart with the “SNOW” covered airplane. The odds of having 3 cowboys in the cockpit is highly unlikely.
I would have waved as well, it’s a nice gesture.