There is no real difference between...

[Inactive]

... cohabiting couples with children and married couples with children.

Why dont cohabiting couples (at least those with kids) just get married?

 

[BebsiBolice]

Marriage is not for everyone.

 

[Apollo]

Marriage has either legal or tax benefits in many countries.

Or sometimes the opposite (negative consequences). Depends on the situation.

 

[Grigori Rasputin]

I think I'm the only one in my city ( Somali) who's officially ( gov) married to my female. Everyone else is "traditionally " married for section 8, tax looting and ceydh purposes.