What's the point of editing rather than deleting spam?

[bobbyi]

I'm not trying to pick on xorbie here because I see this stuff all the time, and it has always baffled me. What is the point of this ?
Doesn't it make more sense to delete worthless threads rather than editing them and having them still there cluttering the forum? In this case, you can still see the url that the guy was spamming from the subject of the reply and the thread isn't locked so people can potentially reply and keep it up and in the way of strategy posts. When I saw this spam on MHS, I just deleted the thread. Isn't that the right approach?