Yes. I also noticed that immediately, Lexico. But in my experience of travelling around East Asia (e.g. Indonesia, Thailand...), policemen are often like that (except in Japan where they are always dead serious). They are usually quite young and don't look very mature or reliable. It seems that they are just following orders and try to have a good time anyway (maybe because there job is boring ?). So I don''t think it's a stunt. I've just come back from Shanghai, and I noticed how police officers there looked so much more friendly and easy-going than in Tokyo. I certainly felt more comfortable there in Shanghai, in a supposedly undemocratic country that doesn't respect human rights, than in "developed and democratic" Japan.
I am very sensitive to people's attitude or "look in the eyes", and feel immediately how people are disposed toward me (i.e. whether they are distrustful, friendly, aggressive, want to cheat me, make fun of me, respect me or whatever). The police with which I have felt the most uncomfortable (i.e. felt quite threatening) so far were in Japan, Vietnam and Israel.