Certified Clean Idle - A Sticker Without a Purpose

A sticker bearing the words "Certified Clean Idle" was spotted on the side of a Semi while stuck on the freeway. This lead me down a rabbit hole of various unanswered questions. Most notably:
Who is this sticker for?
- It's not for the truck driver. The driver will know if it's a 'clean idle' vehicle, and likely won't be standing outside the truck to read the sticker at every available opportunity.
- It's not for the company that owns the truck. If the 'clean idle' qualification is one that grants some sort of tax break or insurance break, it'll come down to the model of the truck. The physical presence of the sticker is meaningless here.
- It's not for the freight equivalent of a smog test. The test will determine if it's a clean idle.
- It's not for other drivers. I doubt my idea of 'clean' and the manufacturer's idea of 'clean' (or the environmental agency's idea of 'clean') coincide to any degree. The sticker does nothing to convince me that it is actually clean. Instead, it only tells me that the tested version of that track passed a test once upon a time.

Why is that sticker there?
I end this with more questions than answers.

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These videos are created without the use of AI.
I believe that using AI as a generative artistic tool will inevitably lead to the downfall of human imagination and ingenuity. In the same vein, it will lead to the utter destruction of whole artistic industries.
Do not hand the power of your imagination to something else.
Who are we when we no longer dream?
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