I just moved across the USA in the last year. In both places I lived, it was actually CHEAPER to buy mid-ranged (20-30 megabit) internet WITH basic cable than it would be to get just internet. In both cases it was 5 dollars cheaper a month as part of a "new signup bundle offer". After 12 months it becomes $15 more expensive to have both, BUT, I was told that I could cancel my television services at that time (and still pay $5 more a month than with the bundle costs).
My assumption is that they are trying to make the cable numbers look better. Note that they didn't show how much TV is actually being watched, only that people are still getting cable services
My second assumption is that they understand the power of laziness and/or non-confrontation. How much work/effort is needed to be on the phone for an hour (or more?) to cancel a service like tv channels while they try to force upsell you new services. I bet they know they can get some percentage of the population to pay the extra money for services they aren't using just to avoid dealing with the cable companies.