Not at all. It's a tool, and one which often requires a fair bit of finesse to pull off accurately.
It can however be used in an immature way, same as everything else. Are nuclear weapons immature? Well they're USUALLY used that way... "don't hit me or I'll hit yeu back >=O " but it doesn't mean the tool itself is at fault.
It doesn't matter if they're right. If they can't proove they're right, then they're wrong. No matter how right they may be.
I think that a lot of people confuse all forms of dry humor as sarcasm, which isn't correct. Deadpan delivery of a joke does not equate to sarcasm. True sarcasm always involves some form of mockery. If you're being sarcastic and your subject is another person, particularly someone in your social circle, then I think it is cruel and immature. You're essentially propping yourself up (by showing how witty you are) at the expense of another.
With that out of the way, I should admit I can be quite sarcastic.