Waste of money and other resources. Unnecessary, for show.
But also I am sure there is more than the for show component.
This is a diabolical totalitarian junta Biden fronts. They have reasons.
The reason for federal vaccination sites is to associate the federal government and its officials with the administration of life-preserving vaccines that are diverted from state, !ocal, and private channels. This builds federal political power and develops a tacit threat that the federal government can deny vaccine doses to those who are out of favor.