Such situation have a term - provocation. Runners are provoked to break the rules (I assume that some runners did it because of lack in ISSOM2007 knowledge - march is rare object during sprint races).
1) First of all: It is better TO AVOID PROVOCATIONS! Recently IOF during seminar at Riga gave a clear suggestion about it.
2) If organizers really like such legs - please, put tape along this coast line to give runners a clear sign: 'it is not OK to cross this territory'. That's a really good practice actually (especially according to flower-beds or other olive situations).
3) Runners who get unfair advantage must be disqualified. By organizers or by them-self. I remember the case when Olav Lundanes made DSQ for him-self during NM-Sprint (I was a main coach in Halden SK this time and actually I still don't think that Olav got unfair advantage - but he broke the rule - that's true).
Almost the same story happened before at World Cup race when several runners crossed red lines without sanctions!
I don't understand: what's the point with these exactions in form of so called athletes licences (with aim to fill IOF Anti-Doping Fund) if there are no fairness in basic things?? #Fairplay #WorldCup2016