That's my point. They are not taxed separately but they do provide liability protection. In your other comment you made it sound like they are taxed separately and that was the cost to pay for being treated like a separate entity.
It looks like I misunderstood your comment. The point I want to drive home is that when the government "backs" one entity, paying for that backing via taxes on net income should not count as double taxation because I consider that tax a fee to pay for that one entity. Whether the government offers some other kind of entity with different tax advantages is, to me, beside the point because as someone who is not a corporate tax expert, I have to assume that there must be some kind of advantage to running a C corp vs an llc.