Satellite centers add an element of permanence and reliability to the neighborhood gatherings concept.
An example is the so-called "multi-site movement" among megachurches. Instead of relying on the one central campus to continue growing, they decentralize their ministry and create additional free-standing campuses that share a common leadership team, a common identity and mission, and in some cases the same preaching on Sunday. Some of the largest congregations have seven or more campuses, each one soon growing to the size of the original campus. By leveraging a known brand, the megachurch grows exponentially.
Smaller congregations can do the same. Their satellite centers might be rented space that is used every Wednesday night while Sunday worship continues to draw people to the one central location. Or Sunday worship can be decentralized, as well.
The point is to get the congregation's presence and unique offerings out where people live, rather than relying on them to keep traveling to a single location.
Those locations, in turn, can develop a style that is appropriate to the context. A coffee house atmosphere, for example, an upbeat contemporary service, or intentional integration across racial and ethnic lines.
Satellite centers involve some expenditures. But their budgets are far less than the cost of expanding the central location to achieve the same growth.