Some people benefit greatly from the services of a professional shadchan, and others do not. There is a market out there for them, and we never know from where a shidduch will come. That said, my three married children all met their zivugim on their own, in HASC, in college, and from our neighborhood.
I met one of my future machetenistas when our kids were toddlers, never dreaming we would end up related. We had sons in the same Yeshiva. I liked her right away, and though we lost touch, 20 years later our children met on their own and married. Be nice to EVERYONE you meet. They may be your relatives someday.