It's well within your rights to go out of your way to be suspicious (eg. obfuscating your user-agent). At the same time sites are within their rights to refuse service to you, just like banks can refuse service to you if you show up wearing a balaclava.
You're assuming too much. I'm not obfuscating/masking anything. I'm just using Firefox with some (to the user/me) useless web APIs disabled to reduce the attack surface of the browser and CF is not doing feature testing. It's not just websites that need to protect themselves.
Eg. Anubis here works fine for me, completely out-classing the CF interstitial page with its simplicity.
