This article addresses the disconnect between the individual policy documents of Mastodon instances--many of which explicitly prohibit data collection for research purposes--and the actual data handling practices observed in academic research involving Mastodon. We present a systematic analysis of 29 works that used Mastodon as a data source, revealing limited adherence to instance--level policies despite researchers' general awareness of their existence. Our findings underscore the need for broader discussion about ethical obligations in research on alternative, decentralized social media platforms.