Most trackers have minimum time after which you can stop seeding, and reseed request system where you are notified if anyone wants a dead torrent to be reseeded.
I recently joined TL as my first tracker and I must say, the quality and seeders are really good. Since they enforce seeding ratios/times and incentivise it, it becomes a self sustaining system.
First time I realised this was when Lilly says "I feel the same about seeing as you do about your inability to hear two people whispering across the room" in Katawa shoujo.
My brother in christ, this joke is straight out of one of the Disney/WB cartoons where one of the portraits of a pig's ancestors is just sausage.