The only people who betched about this were Fox people, of course (O'Reilly named Larry David the pinhead of the week for it and called it "disgusting.")
Look, first, you have to recognize that its not about a religion so much as it is about all these people seeing Jesus in their toast and what not. It had nothing to do with Christianity, per se.
Second, you have to put this in context. If the religion is in the minority in the country and is the focal point for criticism and being mocked, then yes, making them the subject would be more likely to get a reaction. But making fun of mainstream folks, it just isn't as political, under the circumstances.
You want to argue that the threshold for mockery ought to be the same? Well, I won't debate that. But reality is that with regard to making fun of religious people, the two are simply not on equal footing at this point in time.