You guys need to learn not to be so attached to your points! :)
Comments and forum topics are cleared out periodically, and with those, points will be lost. Some of them will be because they are SPAM, others will be because there has been some forum cleaning. Most times however, this should not add up to a lot of points.
Also, randomly flagged comments are not deleted. The admins review the flagged comments before deleting them. So that would not be an issue.