Might be a breed trait. They also go to bed early... usually on the roost before the majority of the others. Early to bed, early to rise? They also lay eggs at ungodly hours. Most of the time they've already laid by sunup. How they find their way to the nesting boxes in the dark, I have no idea.
The last ones in the coop each night are always the red sexlinks and my speckled sussex. It's like they need a personal invitation to go to bed. The sussex probably isn't a breed issue, she's my shadow and will stand at the gate waiting for me to come put them to bed. She also won't go in the chicken door (unless it's an emergency) but waits for me to open the human door for her. And if she's free ranging, forget it. She will wait until it's almost pitch black out, just digging away, then finally realize everyone's in bed and it's dark. She's silly. And I love that little space cadet.