- It keeps conversations short. The receiving line is a structured way for you to say hello to all of your guests without feeling pressured to engage in long conversations. In fact, all that is expected of you is a quick "thank you for coming." It is your job to set a pace and keep the line moving.
- It forces you to greet your guests. If you don't have a receiving line, it is expected that you will mingle during the reception and greet each of your guests. If you leave greetings to happen in this manner, you may avoid speaking with your guests entirely for fear of having to carry on conversations. The receiving line forces you to at least say hello to each guest.
- Guests are expected to introduce themselves. You aren't expected to remember the names of all guests in attendance at your wedding, and you can make mental notes about names that you may have forgotten or faces that are new to you.
- You can make connections. Although this is a time only for quick greetings, some guests will try to start up conversations. Let them know that you'd love to talk with them later in the evening. This gives you ample conversation topics if you start to feel uneasy during unstructured periods of the reception.
- Many guests will expect it. In particular, older relatives will want to congratulate you and your new spouse. By giving them the formal opportunity early in the evening, you can rest easy for the rest of the evening. If you do feel too anxious to stay the entire night, at least you will know that you acknowledged each of your guests.
Source:
Weddings. Yay or Nay? Receiving Lines. Accessed October 19th, 2008.

