Yes it is and you are right. It is used by people who are not Christians but don’t want to create their own system. They use the Christian system but want to dis them at the same time.
And yes it is intended to be.
Sort of like a person who doesn’t like Greeks but uses their alphabet and refers to it as the common letters.
You should have mentioned what an ignorant bigot you are, I wouldn't have bothered with a reply. I'd be surprised if you don't put the very same wheel to work in the very same rut in many a science and history topic here on FR, because that's what trolls do.