That's like asking why I don't throw feces at it while I watch.
Once the invention of the dvr allowed me to skip commercials I haven't watched a show other than sports while it was broadcast. I've even gone beyond that now. My DVR is now basically there to remind me what to download so I can watch it without commercials and at 1.5-1.7x normal speed, depending on the show (ok 1.8x if you count the walking dead). I suppose that'll have to do until I can have things instantaneously beamed into my brain, which really can't come quickly enough for my tastes.
I don't even pay attention to TV schedules anymore. When I see an ad for a new show that looks promising, I set up a OnePass for it. Then, when I have time to sit down and watch some TV, I call up my menu of shows and see what there is for me to watch. I usually have 4 or 5 choices, or more. If some show that looked promising, isn't... I delete the OnePass. I have about 100 OnePasses set up now. I was actually shocked recently when I opened my menu and there were new "Penn & Teller: Fool Us" episodes. I completely would have missed those otherwise.
I LOVE my DVR. Life is so much more pleasant with it. I mean, I can live life on MY schedule instead of one dictated to me by the TV. Ha Ha Ha!