Maybe they can see there's a gap in traffic and therefore no need to press the button? Basically doing you a favour.
In my angered haste I should have said when they are at the crossing, with traffic, with the ability to stop it by pressing the button but don't. I would also do as you say if it was only a few cars to keep the flow.
@D-Dog started
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Maybe they can see there's a gap in traffic and therefore no need to press the button? Basically doing you a favour.