The theory does not actually have anything to do with how many people are willing to abuse a gap in regulations for personal gain, it's analyzing the dynamic between people who would abuse the system for personal gain, and that abuse causing a situation where people will enact vigilante justice against the first group. So people who are self interested will be less likely to abuse the system in ways that mark them as a target. All it requires is that the vigilantism is common and a known factor to the people abusing the system, so that the ways they choose to abuse the system are less obvious. Of course it could go any number of ways based on other factors, I'm just commenting on the dynamics of the interaction here.