1. You can join in them if you have link only. You can't see them on main page.
2. Because this giveaways known only for a little group of people.
3. No problem.

A lot of people don't check the forums a lot or at all, and so don't see private giveaways posted there. Some private giveaways require you to solve a puzzle to enter, so those have even less entries, since you need to spend some time on it.

Of couse man!!!!!

Equivalent of Private Party lounges. You only get in if you're cool enough.

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