It is easy to do these things on a large scale and there is info being broken to the public by insiders leaking it (i a safe way to them). There are credible researchers who have taken samples. There are videos of tankers leaving massive streams in the sky. There is also countel pro being don to confuse the issue. if you look through you will find it.
As far as people spraying dear old mom or granny etc. These things are managed top down just like vaccines with propaganda being poured down as well. Many may think they are doing a service such as countering global warming while the real purpose is hidden from them.