It's not just an idea: http://source.android.com/source/downloading.html
Being that it's an open source project, why wouldn't the carriers have the freedom to add or remove what they want? I don't necessarily like the carrier builds, but they're free to do with Android what they please. That's the general idea behind open source.
I'm not disagreeing with your conclusion that Apple is consistent. And there are certainly closed source Google Apps for Android. But your implication that Android isn't open source is a bit silly.