Even assuming only half of that or 500GB is video, and assuming highest quality at 5GB per hour that is 100 hours of video or 3 hours a day. How the hell do you find time to watch 3 hour of TV per day?
I probably watch a movie or a couple of TV shows per day, so maybe average 1.5 hours. Then the occasional weekend marathon viewing session when I get into something.
I've downloaded some multi-season TV shows accounting for dozens of GB that I have yet to watch. Something for a rainy weekend.
Same with movies. Many, many movies that I have yet to watch, or just haven't yet been in the mood to view yet.
A lot of the pr0n is collected from the day's updates and not immediately watched.
Much of the bandwidth is outgoing. Especially if a particular torrent takes a very long time to complete and I know it's not well seeded, I'll seed it up to 20x.
Many older torrents from public trackers fail to complete after downloading 80 or 90% or more. I'll give up after something sits for a couple of weeks without finishing.
Often, I'll download two or three versions of something and toss out lesser quality versions or else cancel the other torrents when one of them completes.
I throw out a LOT of crap. I'll hear about or be curious about a movie, download it, watch 15 minutes and delete it. (e.g. I started to watch Riddick last night. What a steaming pile of crap.)