I would think that it might not serve a government purpose, but it could serve a social one.
For a lot of societies, care of the elderly is supposed to be performed by the children. A marriage has the implication that care isn't just for their own parents, but the in-laws as well. I expect a divorce like this servers that familial connection, people no longer have to care for their in-laws.
It feels weird to have someone else pick my nose.