Okay, so this whole scenario is absurd, but I'm enjoying the thought experiment. Don't take this post as anything other than fun noodling about -- the fundamental fact is that no city is trying to raise revenue this way.

The simple answer to your objection is that it doesn't matter if you stop at a light for 30 seconds or 60, you still decelerate to a stop and accelerate to your cruising speed again -- the marginal difference is idle time, not decelerate/accelerate time.

"Ah," but you say, "But presumably if the red light is longer, some number of people who would have in the counterfactual world cruised through the green light will instead come to it while it is red, decelerate, stop, and accelerate again."

True enough. But while that light is red, another light is green -- for longer, presumably. So compared to the counterfactual, some cars who would have come down to the stop at the red in the other direction are instead cruising through the intersection.

(I presume, here, that nobody actually just sets the intersection to "all lights red" for extended periods of time. That would indeed increase the gas use of everyone in the city, but it also rather gives the game away.)

Indeed, ignoring the all-lights-red approach, the fact is that presumably however long you set the reds for, the intersection spends 50% of its time red and 50% green (or whatever for more complicated intersections, but the point is, you aren't altering the overall amount of red at the intersection, you're just changing it from many shorter intervals to fewer longer intervals). That being the case, we can reasonably answer whether it's possible to raise revenue at all here. Is every increased stop balanced by a missed stop?

And the answer to that depends on whether it's more or less efficient for overall city traffic to have longer or shorter reds. My intuition fails to provide an answer, and I don't have any formal background in traffic engineering.

But in any case, the difference seems unlikely -- at moderately reasonable red light lengths -- to make drastic changes to the city. At which point the $25/resident/year that I earlier estimated starts to look like a huge overestimate.

TL;DR: There is no conceivable way that cities are cynically lengthening red lights to raise revenue. Not effectively, at least.