Originally posted by DarkEternal:

Ah, but they do serve a purpose.
There is a 20% chance of events occurring every 46 minutes if a player is within 40 meters of at least 3 base structures.
The constant stream of enemies during an event is quite useful for gathering their drops, which in turn have uses in crafting/base building. Not to mention the fact that you're able to get a nice boost in skills for your weapons and blocking skill with your shield.
And, as I said, it's only a 20% chance. Odds are you haven't noticed how many times it hasn't proc'd because well, there's no in game timer and no event happened.

None of that is stuff you can't get elsewhere, though. My problem with the raids is that they happen when I'm building and don't want to be disturbed.