الجواب حامدا و مصلیا
If the principal has permission to use the funds of the college for these such programs, then it is okay for him to spend it on these programs and it is also permissible for those invited to partake in the food and drinks that are provided during these programs. If there is no such permission, then the principal should refrain from spending the funds of the college behind such programs.
And Allah knows best.
