That demo was built specifically for E3. I'm not convinced that a public event will actually destroy part of the environment in the final build. In a persistent world, it seems hard to matchmake people together when some have experienced the colony ships collapsing and others haven't.....unless once it happens it's collapsed for everyone whether or not you were there. I believe what we've witnessed of public events from the latest "infosplosion" is a much more accurate depiction. (Enemies appearing, but not causing destruction to the surrounding environment when warping in) [spoiler]This, for the most part, is conjecture[/spoiler]

They aren't towers, they're colony ships god