HAHA. Thank you for posting that video, that was so cute and funny! Although, I did kinda feel a little sorry for the chick who just wanted it's "Mumma".
My nearly 13-week old 'chicks' were hand raised with their brooder inside the house, I didn't even consider raising them any other way since I got them as day-olds and neither of my two older girls (we got them as point of lay) ever go broody or are the mothering type. I guess you could say they were raised as pets, which is also what they are now - we got them purely for extra companionship, the fact they'll be laying yummy, yummy eggs is just a plus.
They really are just backyard chickens though, we live on a residential block in the suburbs, so we were never planning on 'farming' our chickens other than for the eggs they lay - so we really have no problem with treating them like pets.
They used to fall asleep on my lap all the time when we had them inside, while I would be reading or watching TV, they even used to use my arms as a perch while I'd be using my laptop and sometimes we'd let them wander around the house so they would get used to us big things lumbering around in close proximity to them (we've got tiled floors throughout, any messes were cleaned up easily).
Now they free-range all day, every day and only get shut in their coops overnight. They had no problem at all integrating with our older girls, but that may also be because I had them in the coop next to the older girls' for about a month and a half before letting them out at the same time as the other girls so they got used to each other through the wire. Minimal pecking once they were actually face to face, was all sorted out rather quickly and now they all get along fine.
Now that they spend more of their day awake, they don't like being touched or picked up very much during the day...but about half an hour before bedtime, they both still jump up into my lap to be showered with affection. It's the one time of day that they
love being cuddled and fussed over, right before falling asleep in my lap. They will take themselves into their hutch if I'm not around, but if I am - then they have to get their 'goodnight' cuddles first, haha.
It will be interesting to see if this behaviour continues after they start laying, as I have also heard that a chickens behaviour will change many times in it's first year. Since I'm the only one this happens to though (they won't let anybody else even touch them), I'm not really fussed with discouraging the behaviour as they get older...and bigger.
If they did try to do it to other people though and at more times of the day than just bed time, I probably would try to train it out of them so not to cause any unwilling bodies injury/inconvenience. But just me? I'm more than okay with it.
my chick was so attatched to me but now she is starting to explore and is not so attatched. I wouldn't worry, my chick acted like a pet bird too but she has just learnt about scratching and catching bugs from my older chicken and is now acting more like a chicken. When they get abit older, just go outside and stay with them but let them explore. Don't worry, all chicks are attatched to people 
gh:
