Updating in a corporate environment is very different from what you do at home or a small business. Some sectors require extensive testing before rolling out any change whatsoever.
In that case, they don't want things happening before they have tested any proposed changes.
When a package is blown down to the network with it's configuration locked (and set to not update), they don't expect a package to spontaneously start updating itself.
Google might let their browser ignore "no auto updates," but may find their browser losing market share in the corporate world. If they get booted, chances are 50/50 if the app ever make it back in the mix.
It doesn't take much.
If I wanted a closed ecosystem, I'd have chosen Apple. Google is becoming less and less appealing with every new decision they announce.