I thought they did formal wedding pictures at the church after the ceremony (while everybody else wanders around in the parking lot wondering how to get to the reception) and did the receiving line at the reception.
But I guess protocols vary. :)
Oh...yeah, you're right. They did do that at my brother's wedding. I was one of the ones in the party, so I forgot about the gap.
In our case, the reception hall was right next door, so people went in and gabbed and got seated and all. And the pictures were really quick.