We camp in France in the summer and this year the weather was so poor that I didn't wear shorts at all in the 17 days we were there. We also brought home shorts that the girls hadn't worn. Normally it's the spare jumper that doesn't get worn. Because we take the car it's so easy to take far too much with us.
I generally take enough clothes for the first half of the holiday, having booked a site with laundry facilities, although with small children we have to allow for the odd day with an extra change of clothes. We don't generally go out at night so we don't have to worry about too many going out clothes.