If you don't want to be "spoiled" then don't click on a topic in this forum. If you want to be spoiled on a certain area of gameplay, but not others, then only click on answeres to your question. Don't try to answere someone's question, if you don't want to know more about the topic your just clicked on.

Some people want an answer to their question with as few spoilers as possible... Thus the spoiler tags on major spoilers...

That.

I'm one that prefers answers to a few pointed questions without looking at a wiki for a full walk-through/spoilers. In fact, if I see a name in a topic that I don't recognize I won't even open the thread.

Because its polite. And its better to be safe than sorry.

There's also the feature of the most recent topic showing up while perusing the subsections of the forums. If it's a spoiler in the topic people not even wanting to be in this forum may end up seeing it and having a major plot point spoiled. So it's a matter of being polite and better to be safe than inconsiderate.