In case anyone is still wondering, the reason why that guy suddenly changed his attitude is because at first he didn't see their hair and maybe thought they where suspicious. When the moonlight penetrated the clouds he got to see them.
I'm pretty sure the author is actually nationalistic. This is a WeChat of theirs from a few hours ago.
https://mp.weixin.qq.com/s/9WQc4H_VVmBFrioBpGN_WA