Of course posters are right when they write that trees shouldn't be so easy to destroy. However, if it would be more difficult and would take longer, people would still do it. Just because they can.
In the long run you have no other option than to relocate to a nicer neighbourhood. Even then, the same might happen again and you might have to relocate again. It's the nature of the beast.
The devs made this game with FFA PvP mechanic, thus FFA PvP-er came to play the game. Thus the trees will go down.