We know there is barely any trouble. They're basing their opinion on cardiff fans on youtube videos and peoples ideas of the club from decades ago.
Word of mouth from people that support english clubs and other welsh teams as well.
Cardiff fans = bad. Swansea fans = good guys. Was how it was looked at in my high school in the valleys.
Nothing much factual about the opinion really given many of the english clubs have worse recent histories than ourselves.
Swansea fans carry on banging on about us being "scum", no questions asked. That opinion is getting pretty thin now. No arrests at the last derby if I am correct?.
A few more years in the premier league would do wonders for our image I think. Obviously!.