skysista - how can you calculate the weight of a plane of passengers when you don't weigh each individual????? your point is not valid in this case. There is a size restriction, and there is only so much weight you can get into a bag of this size.
Even when you have a weight restriction of 5 or 7 kilos, do you think the extra weight you add to your handbaggage in duty free is also added in??? 4 bottles of booze = 10 kilos!!