ANtshares has refused to pay its signature campaigners up till now. That is not a good thing to do considering the amount of money they've gathered.
They are not refusing. You're just not following their procedures on how to claim bounty on signature campaign. They are actually process almost 50% of the participants of signature campaign. Just email david about claiming your bounty. His email is in the OP. And fill up the survey form they release for your bounty list. You can also PM me if you want further help mate.

FYI: i'm not belong on antshare devs. I'm just normal investor with some basic knowledge that might help you. I decided to help because i notice that the majority of post here is just a shill/spam and antshare devs is late to response on questions. :/