Ask HN: What seems obvious to game developers but not to web developers?

Over the years it seems the web is becoming more interactive however it feels miles away from an average game’s interactivity and real-time nature. What concepts seem totally natural and normal to game developers yet foreign and elusive to web devs?

I don't write software for either one but I get the idea that game work involves carefully avoiding anything that could slow down the users computer, cause un-necessary traffic on their network, or waste their memory.

With so much of the web it seems like they haven't got a clue how bad the bloated sluggishness needs to be reversed, makes you wonder if the proper skills are even there in some of those places.