I've been looking at floorplans for manufactured homes on the internet -- and for the life of me I can see absolutely NO use at all for BOTH a "living room" AND a "family room". It just makes no sense at all -- especially since they are usually always close enough to each other that TVs in each would interfere with the other. So much space just wasted!

This is so true. Our house has a living room and a family room (connected to the kitchen) and the family room is the most used room in the house, it has many of the kids toys and books, it has our television (we only have one), and it has a few sofas to sit on. But our living room is used for storage, mostly for some of the kids clothes and larger toys, and we also use it as a stroller parking lot since it is located just to the right of our front door, a convenient place to put all the strollers while they aren't in use. If we didn't have that living room, we could probably move all the clothes into other places and fold up the strollers and put them in the garage somewhere instead. What a waste!