What's wrong with blasphemy?

It's o.k for a resteraunt critic to criticise someone for cooking bad food. It's O.K for a football coach to criticise his team (or any other) It's o.k for me to criticise a bad film. But when it comes to sky daddies I have to give it some kind of respect and get told off for criticising jebus. So why do xians get annoyed? It isn't them I'm criticising. Sky daddies obviously don't exist so they won't get offended. Nope, can't see what's wrong.

I think it is a sign of strength. It shows that I'm brave and don't get scared of hell of the being struck down with lighting. Indeed people like Penn and Teller blaspheme and swear all the time and its never done them any harm.