Freethinker's corner

Of late my site here has been hit by numerous messages containing multiple links. I presume these are entrepreneurs attempting to gain audience for whatever it is they are selling. Whenever I see them in my spam box I quickly delete them. I admit I don’t know how this works for them. Does it spread? Does it cascade through my readers? I haven’t received any feedback in days from readers, so something must be going on. Anyone with insight on this?