I had a new 1994 Bessacar with a door towards the rear of the caravan,the door opening from the front. This was to stop the door covering the fridge vents when open. A lot of new caravans, including our 2007 Swift Conqueror, have the door towards the front of the caravan, opening from the front. If the door opened from the rear it would cover part of the front window. Also if you use a porch awning, as i do, the awning does not cover part of the front side window as the door opens rearwards. This allows the side of the porch awning to fit between the front side window and the door frame.
Have had 3 caravans with doors like this with no problems. Providing the door is closed fully there is no problem when travelling and as Trucker says if a door is going to slam to on site it will depend on which way the wind is blowing.
Hamer