What is unethical about choosing which software to use to interpret an HTTP response in a manner of your choice? Is Lynx unethical now? Or disabling Flash?
If you don't want to show content... don't return a 2XX.
If you don't want to show content... don't return a 2XX.
Is it also considered unethical not to install that bundled spyware with your favorite freeware app?
Or how about that trojan installer tried to download automatically when you somehow landed on their page? After all, you used up some of their computing resources by serving you the page, you owe them the installation of their malware.