Tali, To report from earlier in the thread, yo are wrong. Absence actually harms everyone, but teachers are very adept at hiding the harm because they work extremely hard to 'catch up' a child who has been absent, and thus what parents see is 'no problem'.
"In a class of 30 children, if each child takes even 1 week of holiday in term time each year, it works like this:
Child 1 misses week 1. In week 2, Child 2 is absent, but more importantly, Child 1 has missed week 1 and now has gaps in their learning that need to be filled before they can access the work done in week 2. So an adult spends additional time with child 1 to do this, diverting the time that they would normally be using to accelerate the learning of others in the class. This repeats in week 3, when child 3 is absent but child 2 now needs catch-up, etc etc.
What the parents of each individual child will see is 'my child didn't really suffer from being away for a week' (not because the learning they missed was unimportant, or because they didn't miss anything but because the staff did their utmost to fill any gaps after they returned - an often overlooked fact).
Looked at from a 'common good' perspective, everyone in the class suffers (and disproportionately, those children who need most adult assistance to make progress) because adult attention has had to be diverted to this constant 'catch up' process."