Cognitive biases affect all aspects of our lives, including the decision-making process related to the routing of freight transport. In the process of using human-machine systems, people upload rational and objective algorithms in order to obtain the best possible results in the route planning process. Nevertheless, during the route choice process, human reasoning, based on experience and assumptions, overrides the choice of the machine, that is, cognitive biases appear in the decision-making processes. For this reason, we investigate how an objective system of interests becomes a cognitive bias during the process of making decisions related to the route choice of freight transport by motor vehicle. Furthermore, we present a methodology to estimate fuzzy measures of route-related deviations concerning time and distance, which may be indicative of the emergence of cognitive biases.