In a major book on church planting in evangelical life, there is this objection to forming churches in an area in the US: 'another church ... will impede the growth of our church.' This is simply false the authors say, as "when Jesus said "I will build my church," he was not referring to the numerical growth of a particular congregation." In other words, reproduction of congregations following Jesus is the way that the church universal leads more -individuals- "to spiritual maturation." In addition, new churches are not competition but rather instruments to extend the "rule and reign of God" among a people group or city. It is nearly impossible for one church or even several really good churches to reach a whole city, let alone a corridor (several cities). Simply put: people are not doing the same things, they are not in the same place at the same time. This means new churches have an opportunity to branch out into those arenas.
Another objection some raise to church planting is that it "costs too much." The authors of this work counter that there are many ways to finance a new church. It doesn't have to be one church giving all of the effort. Several possible connecting methods of churches are available to help new churches and thus to join up with Matthew 28:19-20 in individual's lives for their joy and God's glory.
One more objection that is heard among pastors at times: it will be more important to "keep daddy healthy." You should protect the status quo, so that the daddy church in an area has plenty of resources. Home churches do not have to look at it this way though. If they are a church with "reproductive DNA" there will be benefits of that which overflow into the home churches. They will have members more zealous about witnessing, it will bring about a kingdom focus rather than something else being the focus, and most church starting help does not "require an excessive expenditure" of resources, but a minor contribution from time to time from the overall blessings of God. One might add, God will also send along more workers to a group that has a heart to start new churches for His glory. This is along the same principle as trusting God with your finances, so that you honor Him and He blesses the obedience even more greatly. There are a hundred principles that could be drawn from this, but that's enough for now.
In short, church planting is not a burden to churches that work together to reach their society better. Especially when one considers the sheer size of suburbs and cities in the USA, there will need to be more than a few churches reaching each corridor for Christ.