I really struggle with the way agents are viewed in a higher regard than the principal and it is very problematic for those who still self manage.
I think it may be simply pragmatic; if you understand and accept that strata manager can only act with the tacit approval of the strata committee, and that committee members come and go, and that some committee secretaries and chairs assume powers that they are not entitled to, then you can see why service providers might prefer to take instructions and fulfil orders from someone whom they know has the authority to issue them.