Agree with all of this.
I have been taking my sons to matches since they were small, my youngest is 10 and we hear a bit of swearing now and again and I am not offended.
Also he has never repeated any of it at home or school. Can you imagine bringing your child up in such a bubble that they never hear it? Doesn't matter how academic they end up, their first day on a building site / newspaper office / trading room would be a MASSIVE eye opener. Repetitive pointless swearing is uncouth. A well placed one adds emphasis.