Who is Publishing Fake Ads for Second Life Pregnancy Roleplay and Why?

Longtime SLer Patchouli Woollahra was browsing Tumblr recently when this ad came scrolling across his screen:

Pregnancy roleplay in Second Life is a fairly popular subculture/activity, but also a very divisive one -- many think it's strange, and it's attracted quite a bit of "WTF?!" mockery among gamers on YouTube and other online forums. So it seemed odd that Linden Lab would evidently feature it as a key feature of Second Life.

Linden Lab, however, says they're not:

"These are not ads created by Linden Lab," company media rep Sheri Bryant told me, when I showed her the screen capture. "Someone else is apparently running them."

So if you see such an ad, I'd recommend not clicking it, because it's a potential security risk. And if it's not from Linden Lab, who is paying money to put them up, and why?

Patchouli did some preliminary research, and has some conjectures: