Kazaa:
It's not a glitch. From what HiTech said at the convention a few years ago, it's a necessity from a programming standpoint in order to make the game playable. From what I understand and remember, the problem is that there are SO many objects on a map that they have to be left unchangeable. If damage and destruction applied to trees, then updates on every single one of the trees would be part of the data that had to be transmitted across the internet.
If you think lag is bad now, you simply can't imagine how bad things would be in that situation! And if the data pipes don't allow for damage to be applied to trees, then THEY have to win every single "collision." It's just the way things have to be.