5. Discussion
Is this the story of a conflict? Apparently yes. From managerial practice, we know that the raise of the performance of the core/ aviation activity is one of the main obsessions of airport policymakers (Doganis, 2006), which means working to increase of the number of passengers year after year. Controlling for other factors, the story told by our data seems to question the mere existence of the non-aviation side as mean to improve profits through revenue increasing. In fact the raise in the number of passengers would cause decrease in NAR, both per passenger and partly per square meter. If on one side this can be somewhat compensated by aviation fees from airline, on the other side this becomes a matter of survival for instance for smaller airports in terms of traffic flows, which should try to compensate the lesser, even negative in some cases, revenue from aviation with the one from commercial sources. However, despite such conflict exists, its consequences are less heavy. After all, if these were major shortcomings, such a big success of NAR in modern airports would not be explained.