Hey Archie — totally get it. It’s hard to compete with the tech giants on pricing, as they’re willing to eliminate almost all their margin to get developers in their ecosystems. Firebase, without being owned/subsidized by GCP would be unsustainable.
You’re right that maybe for the casual developer, cheapest is usually king. That said, when working on a new software startup or business app for a company, time to develop, security, maintainability, scalability, and other concerns become much more relevant than saving $25/mo (30-minutes of a junior engineers time).
Also, just to clarify, the client app users limit is unlimited when you bringing your own auth provider. The 500 limit is for if you use 8bases default auth, which uses Auth0 under the hood. I recommend you hook up your own Cognito, Auth0, Okta, or whatever account so that you can bypass the 500 user limit.
All that said, both tools exist for a reason, though I’ve seen a meaningful number of developers moving from using Firebase to 8base, as well as replatform their apps for the expressed reasons.