To sarcasm or not to sarcasm?

I read that sarcasm boosts creativity and it got me thinking: do I use sarcasm? The answer is a firm "Y"...but that happens only mentally and practically never verbally. It's not like it happened overnight. It takes me a lot of practice and discipline to keep sarcasm inside my head. After all, it's not people's fault that they are not, let's say, up to my standards (but, hey, most of the time even I'm not up to my own standards so it's nothing personal) and to let them be aware of that will lead to no productive outcome so why do it? It's not like people will learn from it and try to do better next time (yeah, I wish). No, it will only make them feel bad - either about themselves or me; or both. So to let sarcasm out of the bottle would only serve my ego, which would be equally ugly as whatever has triggered it. My ego (and anyone's ego for that matter) does not justify that.