I've seen some industry insiders talk about how box-office takings effectively "snapshot" later earnings. So the TV syndication rights or streaming rights will pay out based on the box office (and possibly even just the opening weekend).

Certainly this isn't always true: The Room has been running for a long time, and is now presumably much more valuable than its initial box office would suggest. But I don't think that most movies become cult hits, and their revenue is probably closely related to initial box office.

I don't have a source for this beyond reddit comments though.