I would install a game on my computer, of course, and I would also download a game in the browser, no issues with that. But, when I do run the game on my PC or in the browser a message comes up saying "You need to install XYZ" my experience will be ruined and so I would remove the game right away. Usability is a very important factor for me. Of course I would play Unity stuff if the plugin was included in the browser, this makes it easier for me, the user, to play the game. As a developer, I am aware of alternative technologies -- WebGL, Flash with Stage3D -- which won't prompt me for additional installations and thus showing such a message is a major usability breach. It's like stating: "I won't go to the local bakery for some bread, I'll travel 50 km instead to get absolutely the same thing". It's why people use browsers in the first place, they make things easier. If I want to see an installer I won't play a browser, but a normal desktop game. I repeat again I'm well aware of the advantages the plugin provides.
that follows the line of thinking, whatever the developer of the browser decides. Im alright with it
This has nothing to do with the discussion. I don't agree or use everything the browser provides, but some things are rather useful.