In an industrial setting, making things clean is a messy, time-consuming business. You can sandblast, soak, scrub or grind surface contaminants away, and must then dispose of the waste. And cleaning media needs to be replenished.
Using a specially-calibrated laser cuts several steps out of the process by simply vaporizing whatever surface contaminants need to be removed:
Here's a laser burning a beer bottle mold and a saw blade clean:
And of course laser cleaning is awesome for detail work. When something is too big to soak, like this old fireplace, the only alternative would be to sandblast or scrub. But with a laser you can do it onsite:
The first two videos are by Belgian manufacturer P-Laser while the third is from Canada's ESR Laser. Both tout the eco-friendly benefits of laser cleaning, which is honest inasmuch as there is no need to dispose of chemicals; but the nasty fumes coming off of these parts surely need to be filtered somehow.