It's the usual scenario with these kind of incidents, that there is a flash point that sets the whole thing off.
Hans was excluded in heat 18 for being the cause of the stoppage when Chris Harris took a tumble.
The Sky team showed Hans a replay but they showed a high wide shot, which didn't show the contact.
The referee made his decision off a low reverse angle, which cearly showed Hans' back wheel rubbing against Chris' clutch lever before he fell.
It's a shame the Sky team didn't show the low reverse angle replay, as Hans' and Nicki probably wouldn't have kicked off and the British fans wouldn't have been annoyed at the Danes running to fellow Dane Ole Oleson, to complain furiously, which obviously raised a few heckles.
It's debatable but the Danes furious protests may have influenced the referee's decision to exclude Travis McGowan in a first bend bunching incident in heat 21, where the replay showed that there was clear contact from the mud gaurd of the rider inside him (Lindback but not anybody's fault).
Watching the replay, it felt as though the referee might have been subconcsiously evening up the luck of the draw without realising it.
If the Danes felt that theyhad been unfairly treated and then began gesticulating to a predominantly British crowd after an incident involving a British rider then it's not really surprising that a minority of fans will react in kind.
Hans set the tone by kicking the pit wall in frustration and hitting the camera after the camerman filmed the Danish teams complaints to Ole.
Gesticulating to the crowd in a FIFA football international competition will probably get you pulled in before a diceplinary panel.
Finally the selling of bottles in the stadium at £10 for 4 was perhaps a poor management decision, as most licensed premises at venues and stadiums do not allow customers to drink out of bottles, or take glasses outside.