Intense facial expressions are a big part of the Maori tradition and part of the Haka. In many areas of New Zealand, you’ll see Maori figures carved with their tongues out and traditional dances where the dancers stick out their tongues — sticking out the tongue and rolling back the eyes is common in Maori challenges as it makes the warriors look fierce. The first time I saw a real Maori Haka was in the airport in Sydney — I had gone there for a conference and the Junior All Blacks (rugby team) were in the airport and did an impromptu haka right in the terminal. It was epic! And mesmerizing.
In Rotorua, you can get a peek into the Maori culture at the Tamaki Maori Village. It is a bit touristy, but they do a really good job of sharing Maori traditions with the guests. And unless you have some Maori friends who can take you to a Marae (Maori meeting grounds) then this is probably the closest you can get to seeing what it is like. The pic below is of me and my sister and one of the performers at Tamaki: