You want your family to sit together? fine. You pay for it. I'm with PAXboy on this one, why SHOULD families be exempt?
Because "It is probable that family group members would seek each other out should an emergency evacuation be required, an action that could adversely affect the rapid evacuation of the aircraft. Children should be seated where they can be adequately supervised by an accompanying adult in the event of turbulence or a decompression in the cabin."
That's why, its a safety matter as far as the CAA are concerned.
Quote from the CAA, here is the citation
http://www.caa.co.uk/default.aspx?ca...90&pageid=1344