Wow..read through all these posts. Quite the tempest in the teapot. Anyway my 2 cents.

Have done this numerous times with my wife ( mostly on NW but I think also on CO). My approach has always been full disclosure with the FA. I say my wife and I will be switching off at some point so each one of us can get a little rest while the other takes care of the kids. We know that only one of gets the meal ( if there is one).

I have never had a FA say we can't do this and they have always been appreciative of my upfront consideration and honesty. I don't think this in anyway degrades the integrity of the FC product in anyway shape or form.

The seat is mine by any way I acquired it and if we share in a way that does not disrupt other passengers then its really no one's business but ours.