That seems very odd, kind of rude and selfish and you need to be strict with this parent starting now. Put your foot down, no means no. Why do some parents behave worse than the children? I advise parents not to pick up their children until after 3:30 as well because they sleep until 2:45 or 3:00 then there are the diaper changes and snacktime and I'm super busy for that half hour so adding in a pickup is not easy.