Those were the days ;)

I was under the impression that it's now no longer possible to upload an APK that has been built in Debug Mode to Google Play. I don't know if other app stores (i.e. Amazon App store) are enforcing this.

Yes, the "code" is - it has to be in order for it to be executed. My point is that method variable names are not normally visible.

Proguard is set up to obfuscate by default on release builds with the default build script, but many devs often turn it off or use a different build system without it as a build step. You often need to add exceptions for 3rd party libs that rely on class names or variable names not changing for whatever reason (usually reflection).