I'm online DA everyday, I just don't necessarily post something, but I do check messages everyday and so forth, even if I don't respond to them immediately.
Funny that you mention facebook, I actually deactivated my account the day before yesterday; I just wasn't using it for anything anymore. I also was told recently that facebook owns all the content you post, so if you're posting artwork I wouldn't do that; it doesn't seem safe.
If you are actually native american, then sure you can. If people cannot tell, then for the sake of forum posts like this, it would be good to dress accordingly, or in the case of a native activity, demonstrate the culture in a photo.