Having lived near kea for the past 16 years I can confirm that, if they are not habituated to being fed etc. they take hardly any notice of our activities or property (except they have great fun teasing the dog! lol ). Same with the wekas actually. They regularly wander into our sheds and even the bathroom (which is outside) but have never taken anything.
Up at the last Luminate festival on Takaka Hill there were mobs (10 - 20ish at a time) of the local kea flying around all the time (probably same ones that come to our place) but I never saw them even land down at ground level. They just flew around examining the entertainment below and arguing with each other in the trees.
I was in deepest darkest remotest Fiordland, 26 km inland of Secretary Island, near Hidden Lake and a flock (or I would call them a gang) of juvenile kea harassed us all night, trying to steal our gear and peck the tent.
On the other hand Frank and I were camped near Jordan Saddle one time i.e. not too far from Arthurs Pass and a flock of around 14 kea behaved exactly as deepriver described - thank goodness.
aparently the juveniles egg each other on so they try and outdo each other in what they can do
Are you talking about Kea or feral activists. Ha.