I would guess that there are entities that want a copy of every new torrent that comes out. The NSA comes to mind. Merely the fact that some human bothered to share some collection of files makes that collection valuable to entities that can afford to collect everything.
Ok so I assume you just announced the hash_value but didn't stick around and manage peers. So these other entities came in and fulfilled that role. They're not seeding, they're trying to download it.
I recently started experimenting with DHT and so am familiar with it (somewhat). I haven't dug into the bittorrent side of things too much.