The advertisement of more-specific prefixes provides network operators with a fine-grained method to control the interdomain ingress traffic. Prefix deaggregation is recognized as a steady long-lived phenomenon at the interdomain level, despite its well-known negative effects for the community. In this paper, we look past the original motivation for deploying deaggregation in the first place, and instead we focus on its aftermath. We identify and analyze here one particular side-effect of deaggregation regarding the economic impact of this type of strategy: decreasing the transit traffic bill. We propose a general Internet model to analyze the effect of advertising more-specific prefixes on the incoming transit traffic burstiness. We show that deaggregation combined with selective advertisements has a traffic stabilization side-effect, which translates into a decrease of the transit traffic bill. Next, we develop a methodology for Internet Service Providers (ISPs) to monitor general occurrences of prefix deaggregation within their customer base. Thus, the ISPs can detect selective advertisements of deaggregated prefixes, and thus identify customers which impact the business of their providers. We apply the proposed methodology on a complete set of data including routing, traffic, topological and billing information provided by a major Japanese ISP and we discuss the obtained results.