Okay - one last time.
If accounting rules mean that 1/3 of each sixth form student’s funding goes against school overheads, but you think sixth formers use LESS of that provision than each 11-16 pupil, then why aren’t you up in arms that sixth formers are subsidising the 11-16 pupils?
Are the 11-16 pupils, conversely, subsidising the school’s university application support and careers provision then? They don’t use it, so should it be cut? Or sixth form clubs and societies?
Are the sixth formers NOT using loo paper, lighting, heating, etc.? Do you think those costs are just offset by the 11-16 funding and the sixth formers just get them for free?
No - a proportion of their funding is offset against all the school overheads, whether they use them or not. Same for all the pupils in the school.
As above, the school bursar is not in the office saying “oh, Kayla in the sixth form doesn’t do sports so we’ll take that off her account and put it on Johnny’s in year 11.”