How about adding some form of indication that a post is suspect - that is, someone has reported it to the moderators? The information is there, in that when I report a page I am sometimes told it has already been reported
On a board I frequented a long time ago, whenever there was a spam post. The first member to see it would report the post and then reply to the post with a single word - "reported". This would let anyone looking at the post know there was no need to flood the moderator(s) with a bunch of reports.
On this board the rule is that if you respond to a spam post, you will receive a warning.