A lot of places in Whakatane as well as other small towns and cities dont open for long on a Sunday. Seems to be the same in most of NZ.

A lot of people have mixed views about WHK but it has everything you need if you are living there. Tourist wise I dont think there's all that much to do there to be honest apart from White Island and the dolphin and whale tours. From memory you can also go swimming with the dolphins up there.

There are nice surrounding areas in WHK as well. I love one of their names its something like Opehopepo or something :)