This is an edge case in OSS. Even among software packages used by Netflix and Amazon, few of them were attributable to a single maintainer or small group of individuals. They've long since become community developed projects.
Their open source software depended on or derived from your package. They included your copyright notice with software they distributed. Someone contributed code. Someone reported a bug. Someone requested a feature. Someone mentioned it at a conference. I could continue.
i can brag if netflix is using my X or facebook runs all their stuff with my Y. that can help me land consulting gigs, solicit donations, etc.