This study examines the impact of sustainable practices in the hotel industry on guest satisfaction, with a particular focus on dissatisfaction and negative emotions. Using a qualitative approach, the research employs Netnography and web scraping techniques to analyse user-generated content on TripAdvisor, focusing on hotels with eco-friendly initiatives. The analysis highlights guest responses to sustainability practices, particularly those related to water and energy conservation, as well as communication failures. While many travellers support environmental responsibility, certain sustainable practices, such as low water pressure or temperature restrictions, can generate dissatisfaction when they reduce comfort or are poorly communicated. A core finding is that miscommunication about eco-friendly measures often triggers negative emotional reactions among guests. Although sustainability is valued, guests expect transparency and minimal impact on their comfort. This research contributes to understanding the paradox of sustainable hospitality: consumers endorse sustainability in principle but may react negatively when it compromises their experience. The study offers practical insights for hotel managers on implementing and communicating sustainability without diminishing satisfaction. Limitations include reliance on TripAdvisor data, which may not capture the full spectrum of consumer experiences. Future research could be expanded to other platforms and adopt mixed methods to further deepen the analysis.