Can Bonus Packs Mislead Consumers? A Demonstration of How Behavioural Consumer Research Can Inform Unfair Commercial Practices Law on the Example of the ECJ\u2019s Mars Judgement

Abstract

The use of psychological findings in EU internal market regulation has gained interest, particularly in the area of unfair commercial practices. This study investigates consumer perceptions of bonus packs containing an oversized indication of the “extra” volume in the package, such as in the Mars case. The Mars case serves as a standard reference in EU unfair commercial practices law which is used as a benchmark to determine the “average consumer.” Our study demonstrates how an experiment can be set up to provide empirically based insights on whether a practice is “deceptive.” Results of our experiment show that consumers overestimate the extra volume when confronted with an oversized indication compared to control conditions, which is first empirical evidence that this practice is potentially deceptive.