I have to say that while I don't particularly care about the matter at hand, franpa does have a fair point: "You/they don't need it" is not an appropriate answer. I would hope that the "open" in OS would stretch to being open about what development is for if someone is curious enough to ask.
More to the point, though, making obfuscatory replies like that rather than being up front with people is far ruder and far more infuriating.
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