Oh that's cool - might be some way of integrating that into my site in the future.

One of the core differences though is that TransitFeeds is primarily for browsing and discovering new feeds to interact directly.

The API is more of a value-add so devs can automate their own build processes, or in the case of something like GTFS-RealTime, making the data into a mobile-friendly format (a single GTFS-RealTime snapshot could be say, 2 MB big and contain information for thousands of vehicles).