Friends are important for children. The kids need to mix with other kids, so as to learn about the ways of the world, learn to adjust, know when and how to react and respond, surge ahead in life while keeping oneself safe.
Also, good friends inspire and bring out the best in us. There are some parents who do not allow their children to go out and play with others for fear of their kids picking up bad language, behaviour etc. The recent trend of friends kidnapping friends will only add strength to this approach. If a child is naturally not an outgoing person who loves to stay indoors, it is okay.
But then too kids who are not allowed to mix with others may find it difficult to understand and adjust to the outside world as adults, when they step out into the professional world. So this approach of keeping the children away from outsiders may not be very correct. We need to search for good friends and develop a good circle. But how to judge friends? Here comes the role of parents.