Though I haven't actually played your game yet, I will say that it depends on context. Yeah, having characters that swore at any given chance does subtract to the piece. But sometimes having, at least, grown men saying anything other than a swore makes it strange and out of place if it does warrant it. A balance is needed. But sometimes it's just the wording that others might take offense.
Otherwise the excessive use of curse words would just make one sound childish, I agree. So I'd say don't take to heart those who think like that. After I play it I'll give a more accurate wordvomit. Sorry.