Note that browser extensions are reviewed by humans, as are updates to them. You also need to pay a nominal fee ($5 by credit card) to submit an extension to the Chrome store, to avoid spammers.
Chrome extensions are generally not subject to human review. I maintained one with 50k+ weekly actives for about 3 years and I think out of probably ~500+ updates I had at most 10 go through human review, and most of those were due to a fraudulent DMCA claim (they started doing manual reviews afterward for a bit, then stopped again)