"Bad language" and "inciting behaiviour"... extremely subjective concepts.
Calling someone an "idiot" might be seen as being bad language for some whereas a mouthful of the most fervent vitriol with every swear known to man may be seen as part of the "technical" language of the game to others.
Is it more acceptable at football matches? I would say so yes. It's a release of frustration and pent up emotion and whilst some people go mad, others show restraint. My 70 year old Nannan wouldn't dream of swearing sober in her day-to-day life beyond the odd "chuff" here and there. Get her to a football match and she can swear like a sailor some days. I think that's because football is seen as being a patriarchal activity - and that status is achieved in a male society through aggression. In order to prevent being somewhat sidelined by their male counterparts, this behavior can also rub off on female football supporters as well to show their equal status.
What counts as inciting behavior is also down to individual perception. From a fan's point of view, telling a crowd of 2000 away fans to eff off is not the same as squaring up to an individual and saying it. Sticking two fingers up at a crowd is again, not the same as doing it to one person. Towards the crowd as a whole, I would see this as acceptable... it's an "us against them" battle where only the colour of the shirt is the most important thing - not whether they're nice people really (which in our experience, most football fans are.) C
Change it to the manager of a team telling a crowd to eff off or sticking two fingers up (stand up for your applause Mr Mourinho) and other people may agree or disagree that it constitutes inciting behavior
Anyway... swearing is more acceptable at football and definitely more widespread than in day to day life. You don't give suggestions as to what inciting behavior is (kissing badges on shirts? players celebrating a goal in front of opposition fans?) but I would say that the examples I named are less acceptable at football because of some fans' inability to restrain themselves manifesting in violence.
Swear at a crowd in town and you'll get people telling you off. Swear when you're in a football crowd and hardly anyone will notice.
Kiss the badge on your shirt on High Street and hardly anyone will bat an eyelid. Do it in front of 20000 opposition fans all baying for your blood after your team scores, you're in trouble.
Hope that helped and if it doesn't... mention Marx. That always gets you points.