I totally get what the OP is talking about. For instance I have Office Pro, and they added support for Android Wear so now it loads to my watch and I have no reason nor do I want it on my watch.
Unless you root the watch, I do not believe there is any way to stop this. The block in the Wear app is simply, at this time, to block notifications from an app.
This is a potential issue and I believe Android will need to address this soon, if said app maker decides to add Wear in their app, they may or may not even test it, so if there is incorrect application and the Wear addition begins query to the phone, with nothing to find, it could end up killing battery life. Another situation that will eventually come up is limited memory on the watch compared to how many apps on the phone that have Wear included. These are even beyond the idea, that the end user doesn't want, said Wear app, to load.
For both reasons, I believe they "Android Wear" needs to add in the Wear app another section that controls apps loading to watch.
about the links above,
The adb method is cumbersome and if you should restart your watch I wonder if the app would just reload?
The app Wear App Manager looks good but should basically be implemented in Android Wear.
