I alternate between working days and nights so do pop on fairly regularly in the early hours. Sirus is also on pretty regularly too. Aswell as the spam that you guys do get to see there is also around 30-100 other spam posts a day that you don't see because we delete them.
ALthough most people are pretty good at hitting the red triangle there are still a number of people that keep quoting the spam. These people are actually helping the spammers by doing their job for them. Added to that are those that haven't yet worked out that reporting the post is better than replying to the post with summit like 'spam' or ':nospamhere:'.
We'll never get rid of spam completely but with your help hopefully we can minimise the impact and 'air time' the spam gets.