Case study based on Interactional Sociolinguistics principles, dealing with a micro-analysis of talk-in- interaction to investigate the defeat of expectation in the institutional discourse of a call-center service for classified ads. Data generating methods include field notes taken during visits to the company premises and interviews with some of the staff members; marketing research documents reading procedures and telephone call-service recordings and transcriptions. Data analysis has shown that the defeat of expectation built up by the public is due to cognitive dissonance between the actual vehicle practice and its publicity, as well as conflicting footings and asymmetrical alignments concerning the customers. Alongside linguistic traits, evidence of ethical and marketing aspects in this kind of institutional interaction points to the centrality of business ethics for more responsible management and better quality of life.