The fact that the people running it are all respected members of the community with solid reps probably helps. Regardless, we haven't actually had much interest. These sorts of returns aren't that enticing in this space.
Re: trust, the blockchain does not eliminate it at all. If I purchase something off you with SBD, I have to trust that you will post it. Even if it's a digital good I have to trust that you will send it. If we want to remove that we need an escrow service/middleman. Smart contracts may change that, but you are still placing your trust in whoever codes the smart contract, network, etc.