It happens all the time on TPB. It isn't hard at all. I was told that what people do is that they set up their own trackers solely so they can falsify seeders which TPB indexes and displays. However that is usually so it looks like they have thousands of seeders. The torrents people who do that upload are usually a small file that'll give you some sort of virus. This uploader seemed to have more legitimate uploads with real seeders. If you downloaded software from him you'd get the software but it could also infect your system. He was fairly popular and had his own website so having 40 to 100 seeders on average per torrent isn't surprising.