To prevent "skunking". Also, because people would pay a price premium for it - sort of like the way white eggs were all the rage in the supermarket, until suddenly the public decided brown eggs were "fresher". Because the American public is easily manipulated - as this whole conspiracy theory experience amply demonstrates.
Related, you can "carry" information with light by manipulating the light itself. Its possible (ain't physics great???) to push a satellite with a laser beam, or to use lasers to deposit paint/ink (by superheating the ink until it boils off in a desired direction) - but I am unaware of any process using light to push a substance through a solid object without perforation, and few substances take those sorts of temperatures well.
A crazy conspiuracy theory should, in my view, pick a more plausible delivery method.
Or, you know, "magic". I hat e that widespread ignorance has been raised to such a lofty pedestal that its seemingly sought after as a desired state.
"I don't know (....), but I think that [....]" is NOT the desired state of conversation. It should be taken as an admission that everything the speaker has to say on topic (....) is likely worthless, unless they should accidentally get something right. An opinion on facts has no independent validity. Worng is still wrong, no matter how earnestly the speaker feels about it. More "I don't know (....), so I'm going to look into it further" would be GREATLY appreciated.