I was talking about a case where there are cars behind me. And it's "unnecessarily" only legally, but most drivers understand this as a driving etiquette in congested traffic.

Picture two streets joining together, both with long lines of vehicles in them. One of them has right of way, the other one doesn't. When everyone drives "passively aggressively" (like Waymo is being described to), an opening never shows up, and "yielding" cars wait until the rush hour clears up, causing people in that street to go bonkers.

This happens quite frequently in many old European cities I've been to in the rush hour or when anything unusual happens (because there are no alternative routes and streets are tight: like a crash or broken-down car ahead might cause this with lots of traffic). Not sure how much it applies to Waymo and SFO, but I can imagine it certainly happens in some areas.