Chickens on Pasture

After about 4 weeks old, the chickens, Jumbo X Cornish Cross broilers, have enough feathers to live outside without supplemental heat.  They are also large enough (I hope) to deter attacks by hawks.  Although I lack a secure chicken house on pasture in which they can spend the night, so I'm still having to carry them back and forth from the chicken house to the pastured area, at least they can roam about all day without supplemental protection.  Here's a video of them enjoying freedom.They are inside electrified poultry netting.  I opened the door to the chicken house in hopes that they'd roam about and find their own pasture, but they really just don't want to move.  They'd rather sit in front of the food container and eat.  When I take it away, they move more as they look for something to eat.  This breed is not like my "normal" chickens, who are never still unless they are laying an egg or taking an afternoon nap.  The rest of the time the "normal" ones are chasing bugs, scratching in the mulch, or just walking around.