I fail to see this as any more harmful than the auto updating feature. I understand the concern of multiple avenues to phone home as being worse than one, but it's negligible considering it's the same company. Coupled with all of their other services for security incidents, prediction, auto correct, spelling, usage stats, dangerous page warnings, etc, I think it's just another log on the fire and not worth being concerned about specifically.
It actually is almost nothing like the auto updating feature.
Finch is mainly used for A/B testing. It doesn't push actual updates, all it does it turn existing features (flags) on and off. It's used for quickly A/B testing or incremental rolling new features and is designed to be more agile.
if you have a logged-off cookie, and the publisher can associate you with a logged-in user at a near point in time, they can charge you as logged in impression.
The biggest difference I see is the speed. You're right, it doesn't make a difference from a technical point of view but it illustrates again just how much power they have over chrome - and thereby over the web: They can push a policy update to the bigger part of Chrome's userbase in 24 hours.
It should be entertaining when car makers use the same strategy: "Oh yeah, we have this system where everytime you turn the ignition, your car polls us and updates its assistant, motor, steering and airbag settings. Don't worry though, we mostly just use it for randomized tests and field trials."
