I don't have a TV. As it happens, in my current situation, I couldn't have one if I did want to, which I don't.
I do watch TV shows. We have a Netflix account, before which we had a BBC iPlayer account. We own and borrow box sets. But at home when I watch a television show, I am doing it on purpose. And that, to me, is the key difference between me without a TV and me with a TV.
When I'm visiting somewhere that has one I find we end up watching the least bad thing on. The same thing used to happen to me when I had a TV. You have a time in your schedule, consciously or not, that says 'TV'. You fill that time with whatever is on. You pay various companies money so that you can have a large variety of choices. And you choose whatever is best from there. Not watching TV at all only becomes an option when really isn't anything on that's even passable. Given the tendency of tired people who've been making decisions all day to take the easiest path, that bar can be pretty low.
To put it another way, for me, the difference between not owning and owning a TV is the difference between watching Firefly, or The Blue Planet, or Avatar and 'watching TV'. There are plenty of shows I like. But I don't like TV. I don't like half the stuff I end up watching in other people's houses. Yeah, a lot of the time I get into it and I keep watching because I want to find out what happens or whatever. But that's not the same as coming out the other end really glad I spent that time that way. And I don't like ads. There are a now, I understand, many ways to record it and/or fast forward ads. But I haven't come across one that's less effort than streaming the show or watching it from a disk in the first place. Not to mention the price.
On the other hand, to mention the price, Mr. Money Mustache covers it quite nicely. TV is expensive. Organising it so 'the best thing on' is actually decent costs even more money. Way more money than an account with Netflix or BBC iPlayer or something. Heck, for the amount of money most people spend on cable, or satellite or whatever, I could more than afford to buy pretty much all of the shows I actually want to watch in box sets.
I get the question 'what do you you point your furniture at?' from people I tell that I don't have a TV. We point our furniture at tables. Then we put things on the tables.