"If your belief/non-belief makes you feel like it's acceptable behavior to insult others by calling them superstitious or sinners - it's wrong."

Those who harbour superstitions are superstitious - it's as simple as that! I certainly don't feel guilty about 'calling-a-spade-a-spade'. Who said anything about sinners?

"And if I want to believe in an invisible old man in the sky it shouldn't matter to you."

It doesn't - unless, that is, you go on and on and on about it or try to convert me or others - particularly children - to your obsessive and unsubstantiated beliefs.