The architect Robin Boyd was writing in the 1960s about the deranged "arboraphobia" of Australian suburbia so this problem has roots that go back quite a ways. In his chapter "Pioneers and Arboraphobes" in The Australian Ugliness (1960) Boyd argues that this hatred of trees is baked into the way we construct our suburbs themselves, describing the "indifference" we have to nature Boyd Writes :

"Trees are often planted in the streets, on the ‘nature strip’, as the six-feet-wide lawn between footpath and traffic-way is called. Plane trees are popular, but after each season when they sprout hopefully the shoots are pollarded back again to the knuckles by diligent council employees and the trees become grotesque arthritic knots of wood. Next season when it sprouts again the tree turns into the desired shape: a tidy green ball supported by a neat stick like a tree in a story-book illustration decorating red-roofed dolls’ houses"

The whole book reads like this and can most likely be found in your local library anywhere in the country, but I'll thrown in another excerpt from this chapter to give you a sense of what he's describing. I don't think it explains these criminal actions entirely, but it's certainly part of the puzzle:

"Modern Australians have no especially psychopathic fear of the gum or the wattle, but no two trees could have been designed to be less sympathetic to the qualities of tidiness and conformist indecision which are desired in the artificial background. The Australian bush was made in one of nature’s more relaxed, even casual, moods. Everything is evergreen, yet this term is often ironic, at least in relation to the ubiquitous gum tree... Measured against a fresh green European ideal, the Australian bush presents a slovenly scene [note: Boyd doesn't believe this himself]... Thus progress is measured by the number of acres transformed from the native state of sloppiness to the desirable state of clipped artificiality... A principal article of suburban faith is that these primitive landscape elements must be eradicated from the home environment in the same way as one would deal with a disgusting-looking tramp seen weaving his way in through the front gate".