One of the best reasons to fellowship with one another is to build up each other's character, to help form Christ within each other that he may be known without each other. We should all be seeking to become as Christ-like as possible, but this is not usually done in most church "services", because it can only be done in intimate relationship with one another. In a typical service,  the focus is on the worship leader and the pastor. Each member of the flock is encouraged and invited to receive what they can from the service-  each comes to be fed, to be touched in some way, and to worship, but the pastor is there to feed the flock as a whole, he is not required to personally disciple individuals-  his focus is on "the flock". He may do one on one counseling, occasionally, usually in reaction to a crisis situation- but even then, he is not in a personal relationship with the counselee, but rather in a professional one, that of pastor to congregant.

So each member comes to the service to feed themselves- the focus is not on fellow sheep, unless there is a brief moment to greet and sometimes pray for each other but they may or may not be in a personal relationship with each other, but most likely not. In some churches, personal relationships are discouraged,  if they are not under the supervision and control of the leadership. If the Bible is discussed without an approved leader present,  a false doctrine might slip in (false doctrines being defined as any teaching they don't agree with, Biblical or not).

The point of all this is - The apostles became Christ-like by daily fellowship with Him AND WITH EACH OTHER, with fellow disciples of Christ, not man. Following Him together, wherever He led them as a group, receiving whatever HE taught them as a group. They did not meet with Jesus and with each other once a week or twice, no, they "continuing daily with one accord in the Temple, and breaking bread from house to house, did eat their meat with gladness and singleness of heart. And the Lord added to the Church daily." He added to "The Church", not a church, His Church, not any denomination but His people, in daily fellowship with one another, in the Temple and house to house, breaking bread and eating meat together. Why shouldn't our church buildings be open 24/7 for believers to use? Why shouldn't our homes be open to one another, daily? This would go a long way to causing Christ to grow strong in each other, and to properly care for those He adds "such as should be saved"...babies need a lot of attention! And older siblings are supposed to help raise little ones, not just mom and dad.