Many of the CS restaurants don't have a kids menu, so they can just order from the adult menu.
Most CS cashiers never check to see who you are ordering for, so many people report buying adult meals for the child anyway and they aren't questioned.
Many people also report just not bringing the kids to the counter with them, so there is never a question about who the food is for and they just order adult meals.
Notice I'm just saying what others report, rather than offering my opinion? Gotta do that around here or you get flamed.