Why do people start questions out with "Athiests:"?

Usually it's there to target to question to a section (in this case Atheists) with the intent to antagonise them and evoke negative reaction

e.g. "Atheist why do you never change the oil in your car until it's too late and then the car is fit for the scrapheap"

They are not actually interested in the answer, but in effect it's a roundabout way of pointing a finger and saying "All atheists never change the oil in the car and therefore knacker their cars up" Of course it's not true and that's what antagonises people into responding.

So you see that in R&S but it's not isolated to that category but happens all over e.g. Politics - direct a lot of question so Cons/Liberals

It's not a way of attempting to move to another category but a way of justifying it's existence in that category (because of course oil changes really doesn't have much to do with R&S and would be better placed under Cars, but then they wouldn't get the negative attention thus defeating the object).

A question that starts with "Atheists:" is usually an attempt by religious trolls to anger a specific subset of users in that category, or it's atheist/anti-theist regulars who're treating the R&S category like a forum (i.e. posting chat violations and user call-outs)

I don't think it's a form of trying to manipulate the Yahoo Answers sorting algorithm, seeing as how there's the category switching option, and a question containing the word "atheists" is likely to end up in R&S.

There ARE a lot of folks in R&S who are sticking questions into random categories. Some put them here in the YA section in the hopes that something will be reported. Others shove questions they don't like into a completely unrelated section.

Cause that's basically who they're trying to annoy/anger