For the record, Mozilla didn't get any money for the Mr. Robot tie-in: it was supposed to be part of a mutual cross-promotion campaign. I don't think the original Pocket integration was paid, either, though my memory there is hazy. Either way Mozilla now owns Pocket anyway.
Mozilla never directly received money for the Pocket placement, however they did get a piece of any premium sign-ups made via the Firefox integration.
If you rule out Firefox, there's hardly any viable option for a modern, feature-complete and freedom-respecting browser. Chromium is OK, but those suspicious blobs don't look very appealing.
For me the most shocking part is that the FSF has a Firefox ESR fork, IceCat, which is hardly maintained and goes 2 versions behind mainline. They don't even bother patching CVEs...