I get it, I do that with junk mail. Perhaps I would read through what i saw as junk mail, if there was a passionate person who really cared about it enough to discuss how it really changed their life in some way. I could be convinced they were worth listening to because they respect my opinion and my time. Respect is the great adaptor for challenging ideas and sharing knowledge. Without respect, ideas cannot pass effectively. The greatest respect is shown through a willingness to also have an interest and listen to my ideas or beliefs. So far, it seems junk mail is only a low cost way to mass market products and services for businesses. The motive seems pretty plain and simple.
There have, however, been passionate people who have come to my door and I do hear them out, and I let them keep coming to talk more and discuss their ideas. Eventually, their passions and motives are made plain and we have a sort of mutual respect for one another, even without agreeing about everything we believe. I am not threatened by hearing or reading about different beliefs and ideas, and I love being around others who have a similar confidence or curiosity about what others think and believe, and what their reasoning is to come to such a hope or certainty in their view.
I only hope to come across this way to those I write to online as well, because there is a sort of coldness to digital communication that many times is taken as disrespect or condescension. I aim to both love and to understand.