The sustainability of music festivals has gained increasing attention, reflecting broader societal concerns about environmental responsibility. While several sustainability protocols exist to provide guidelines for reducing the environmental impact of events, their adoption remains inconsistent. This study examines the alignment between sustainability protocols and the actual practices implemented by music festivals, identifying key gaps and emerging best practices. The research employs a comparative qualitative analysis, using a structured framework to systematically assess both protocols and real-world festival implementations. A distinctive aspect of this study is its collaboration with MI AMI Festival 2025, allowing for direct validation of theoretical insights in a real-world setting. The findings highlight critical gaps in long-term strategic planning, social inclusivity, and transparency, alongside emerging best practices in waste management, energy efficiency, and sustainable mobility. A strong variation in the depth and scope of sustainability practices across European countries is revealed, with Northern and Western European festivals demonstrating higher levels of implementation and transparency. Additionally, the European Green Festival Roadmap 2030 and the Green Festivals and Events through Sustainable Tenders emerged as particularly comprehensive and applicable protocols, offering concrete tools and solutions that remain underutilized across the broader festival landscape. By bridging the gap between policy frameworks and practical applications, this research contributes to the development of a standardized sustainability model for the festival industry, with potential broader applicability.