a) Ribbon cutting ceremony of roads, bridges, amusement parks are primary role of mayors or local government officials, not essential role of a President or PM. However, visiting mass displace families due to disasters or causalities is primary function of a President or PM.
b) A President might be invited to attend such events but in time national crisis where thousands displaced, unsheltered, exposed to hunger the #1 role is supporting them and channeling resources to secure safety.
c) Depends what PM of a country one refers to. In case of Africa, cheap fame and propaganda of the President/PM comes first and the people second or at last, but in the democratic world of the West, citizens first. The President serves the people not himself.
d) When morality and priority are misplaced, usually the money spent on the inauguration ceremony itself and ensuring safety of such official is more than the money spent for the completion of the project ( park, road or bridge) ለ10 ብር ዶሮ የ15 ብር ማሰረያ