I can think of two reasons pretty easily. I post a thread, a round-table discussion for parents, every Friday morning. I ping over sixty FReepers. Then I go do my shopping, finish my laundry, take care of the mail. I check back on the thread while I eat lunch--hours after posting.
Every so often, I'll post a thread apart from the round-table. I usually wait until there are several responses before opening my big ol' mouth again. Take a look back at the first fifteen or twenty remarks that Sarah received. Maybe she is thin-skinned. Pondscum's comment alone would merit some pretty tough armor. If what Sarah posted and FReepmailed is true, she is a woman in a very vulnerable state. How nice that so many compassionate conservatives showed up to stomp on her.