Take A Number? For What?

The numbering system at the Social Security office really baffles me. I walked into the office where I saw a long line of people who were waiting to see one of the clerks. I was advised to take a number and either choose to stand in line or sit down. Because of the baby, I decided to sit down. Then lo and behold other people start coming into the office and they joined the line without selecting a number. What a waste of paper? The SS office never called any numbers as I sat there waiting my turn. And this confused me a lot since instead of them calling me to the window I had to rely on memory as to the person who was in front of me. Then when I get in line, it would appear that I was skipping my turn. So much for order.