"Your game doesn’t need to be in the iOS App Store or Google Play to be played on mobile devices. That is a huge benefit. Sure, it’s good to have it in both of those stores (and is easy enough to achieve), but the fact that it can be played without requiring an install and the extra bulk of the stores is a big opportunity."
I don't know if this is true though. Consumers expect the games to be in the appstores. I don't know anyone who even knows they can play games on the phone browser.
The point I'm trying to make there is consumers can still find your game through those apps like WeChat, and through shared links on Facebook, Twitter, etc... The same way people typically find and consume other forms of content.
What needs some work is making those games stickier in the sense that the person will play it again. That requires saving it to the home screen which probably not enough people are familiar with - and is a bit of a pain on Android.
I like the approach Firefox OS has taken with saving/installing apps and hopefully Apple and Google follow suit. As is, I think iOS's "Add to Home Screen" is fine. Android's like I said, could be improved.
The other thing that needs a bit of work is HTML5 performance in the webview. On iOS at least, game's don't perform as well as when they are played in Safari (since the webview doesn't use the Nitro JS engine) - hopefully that changes soon.
The nice thing about HTML5/JS games is that if someone hears about your game on a website or through word-of-mouth, they can immediately start playing it just by clicking a link. Not much additional thinking is required other than "go to this site on your phone to play."
The type of consumers who wouldn't be able to figure this out are more geared toward casual games. If you are catering to casual gamers then I somewhat agree that you are forced to be complicit with the app store publishing model.
However, more serious gamers are more understanding and are willing to go through minor hurdles, such as using their phone's web browser, as long as you are offering them a more serious game experience.
I don't know if this is true though. Consumers expect the games to be in the appstores. I don't know anyone who even knows they can play games on the phone browser.