The global advertising system is increasingly shaped by two concurrent pressures: persistent inflation and the rapid integration of generative artificial intelligence (GenAI) into advertising production and media management. This study examines the trade-offs between advertising cost efficiency, consumer perceptions, and downstream communication effectiveness using Transaction Cost Economics, the Persuasion Knowledge Model, Signaling Theory, and Mental Accounting Theory. Study 1 applies panel econometric modeling to data from 184 advertising agencies and marketing enterprises to assess production and media-placement efficiency across different Consumer Price Index (CPI) regimes. Study 2 employs a 2 × 2 between-subjects experiment (N = 512) comparing Human-Created and Disclosed GenAI advertisements under neutral and high-inflation salience conditions. Study 1 shows that GenAI adoption reduces production costs by 44.6%, although higher inflation weakens the acquisition-efficiency benefits of predictive advertising. Study 2 shows that AI disclosure increases perceived manipulative intent and reduces perceived authenticity, particularly when inflation salience is high, with adverse effects on brand trust and purchase intention. Overall, the findings provide an AI-enabled managerial decision-support perspective for balancing production efficiency, acquisition performance, and consumer trust when making advertising resource-allocation and human–AI deployment decisions.