In the early days post-independence, they would have been useful avenues for the leader to forge national unity. So Jomo Kenyatta would have been visionary to, for example, celebrate each holiday in a different locale and preach the same stuff Nyerere was doing in Tz; as far as national unity went.
Moi tried to do that, though actions never quite matched words. He also kept them in Nairobi. Nevertheless, though still ethnically skewed, his were the most nationally representative administrations. NARA government might also be in that league.
In the present circumstances, they are indeed a complete of waste of time and money.