It's common, but it's more like "this is common at young companies where the cost of maintaining staging can't pay for itself in improved productivity, because

It's common, but it's more like "this is common at young companies where the cost of maintaining staging can't pay for itself in improved productivity, because there aren't enough engineers for a 5% productivity improvement to be worth hiring multiple engineers for." I'm sure that at FB at one point there wasn't a staging env. Today at FB there are multiple layers of staging, checked automatically as part of the deployment process. I'm ex-FB as well, and we definitely used staging environments every single day as part of the ordinary deploy pipeline. You probably worked there when it was younger, and smaller, and the tooling was less advanced. Large tech companies have advanced dev tooling; eventually, the cost of paying people to make the tools is paid for in productivity gained per engineer, with large enough eng team sizes.