I'm sure it's all just a tale of exaggeration 8 men could easily move an F1 car, but chances are they didn't follow protocol by moving it, which is the moral of the story...
Well F1 cars are roughly minimum 600 kgs, but don't forget the added fuel at the start of the race. Not too sure how much that would add to the car. Anyway it would be easier rolling the car by its wheels - if it had any - but really, who cares after all the exercise the marshalls have done since they were 20, no wonder they'd be struggling to carry 600+ kgs combined.