I must be work obsessed as I do much more than that misshelltoe!
The way I see it is that teachers are paid over the year, work is not just limited to school days. I also usually need to work at some point of the weekend to plan or mark.
We had a snow day this year, I worked from home. Some parents complained as they saw teachers christmas shopping! I'm really not surprised I would have done too!
However, my dh is not a teacher, he often works late or needs to take client calls in the evening or the weekend. It's all relative.
He is also restricted to what hols he takes due to busy periods and working abroad. So between the two of us...nightmare!
Other people can only take hols at a certain time too. Not sure if op is being tongue in cheek or not and I'm rambling! 