I lied. Two comments.
That swearing should apply with or without kids. Last year, we had three kids inside, and another guy had two kids. Three guys came in, and immediately it was F this and SH that. My friend told them off, and as they started to come back at him, nearly everyone in there told them to shut up or get out.
As a long-time sports official, I heard a lot of swearing as "part of the game" or when someone was frustrated with what had just happened (heat of the moment), with nothing personal. If it was directed toward someone else, in a personal manner, they got the gate. Many people take swearing as a normal part of their vocabulary, but a little common courtesy says there are places where the swearing should be set aside, and anywhere there are kids is one of those places.