Just to put my oar into this murky pool of unsanctioned absences from school for holidays. As a past governor at two schools, both primary and secondary we had various courses to do with attendance, and there is plenty of well founded evidence strom studies that shows how even bright children can miss out on most aspects of a planned curriculum by missing a week of work. Beyond that there is the fact that in many cases the whole class is affected becasue the staff often have to divert from the scheduled topics to bring the child who has been absent back up to speed. This is one of the reasons why legislation was introduced that allowed the schools to initiate the fines.
Schools are put under great scrutiny by Ofsted, and issues of unauthorised absences, cause lowered class attendance and attainment scores are both criteria that act negatively towards an Ofsted inspection outcome, - and it has been seen, how that can have serious consequences for the Staff and the whole school.
The idea that travel widens the child's life experiences is rarely upheld when holidays are investigated for educational worth.