But they don't. We have some very very very fine games that you can only find on PC. (Also not everything on your list are console exclusive, like GTA which will make it's way to pc, and most of them are exclusive to one console so I'll be missing out on them anyway.)
1) project cars - I think it's supposed to be coming to the next gen consoles but it's being developed first for PC.
2) star citizen. It's from the maker of the old wing commander games. It's a space sim and while it's still in development, google it and tell me it's not "quality"
3) The ARMA series. If you want realistic tactical shooting, this is the series to go to. Blows the doors off battlefield in terms if realism
4) Path of exile. Sometimes called diablo 2.5, this game has a ton of customization and is just loads of fun to play
5) torchlight 2 - along the same vein as path of exile, this game is actually made by many of the original devs for Diablo 1 and 2. It's faster pace and not very graphically intense but it's a ton of fun (my engineer explodes everything)
6) DOTA2, League of Legends, and SMITE. Pretty much the entire MOBA genre belongs to PC and that leads me to
7) the entire RTS genre. Halo wars tried it on 360, but RTS is a genre meant for PC.
8) DayZ. How could I have mentioned ARMA without mentioning DayZ? It started out as a Mod and then the one guy who created the entire mod was hired on as a developer for the company. The alpha is available on steam and once you buy the game it's forever yours.
9) civilization series. Turn based strategy. Great fun and extremely high quality. The console has some spinoffs but it's not the same as the actual numbered games.
10) SimCity. The flagship city building Sim. PC only.
11) Just Cause 2: MP Mod. Some mod developers decided to take Just Cause 2 and give it the GTA online treatment on steroids. The result? 5000 people servers on the island of Panau causing havoc anyway they deem fit. (which, btw is somewhere between 4-5 times bigger than GTA5)
12) Garry's Mod. The ultimate sandbox game. What you want to do is up to you and it's only available on PC.
Here is a list if QUALITY PC exclusives. It's by no means comprehensive and I didn't include games like skyrim and minecraft that are best played on PC And has amazing mod support.
I'm thinking about making a thread on this topic as it seems to be a common misconception about PC gaming (along with it being ungodly expensive...it's not). These games you mentioned are highly marketed as most of them are exclusive to one Console and that console is vying for your attention. Many of the games I listed are indie developed games. They don't the the marketing budget of MS, Sony or Nintendo behind them. Hell they don't have the development budget that BF4 does but they still produce a great product.