The "human infrastructure" is already here. The Salem sales folks are most likely still in town. The PD and air staff have not announced their new jobs. Salem might even let you "rent out" the existing studios. KLove usually just buys the signal. I bet Salem would even let you use "the Fish" for a small fee.
That infrastructure doesn't come for free. Any new expense has to be budgeted and has to be attached to revenue. Let's say for example Cumulus decides to blow up one of their formats and replace it with CCM. They lose all the money the old format made, plus they have to pay severance to the old staff. Then they have to pay to hire the new folks. Then they have to wait a few months before they get consistent ratings for advertising. That's what I mean by infrastructure.