"Members such as HTC have gone off and added lots of their own software and customizations to their Android devices without contributing any code back to the Alliance"
That's not true. HTC added sense UI on top of android. They are 100% allowed to do that. Android is licenced under the GPL, and HTC came along forked it, and added their own stuff to it, then released the source code (http://developer.htc.com/). The alliance is free to take whatever HTC does and merge it into the android core if they are so inclined.
I'm not buying that carriers and are gaining 100% control of the software. They are legally bound to release the source code. That would have never happened before the open software alliance and android, ergo, the OHA is not "in shambles", and is working as intended.
Carriers are free to charge for whatever services they want to provide. The market should take care of most of that. If sprint wants to charge $30 for tethering, but T-mobile will let you do it for free, then it's advantage T-mobile.