Well, it's more that eggs are kind of congealed bits of co-mingled Grace. A bunch of angels feels the need to get together, mingle Grace, and bury the results in a defensible place until the new angels emerge.

I figure angels are precocial -- they hatch, they can walk and talk and obey orders from the get-go. They would look to the older generation for advice and guidance, of course.

But yeah, it would lead to a very different way of arranging one's society, wouldn't it?