@Yellowdog There is also this possibility. See the “related” section over there? Spammers could assume that the related section is for popular questions, considering that some threads being displayed have a good amount of posts. They could assume that the related section works the same way as the recommendation section on Youtube. When you do marketing, if you don’t target places with “ideal” audience, at least target places with a high concentration of people. I think so, because I used to look at the same place when I was a newbie. I just offered real answers instead of spamming :D
Keep in mind that a lot of spammers don’t speak good English, and many of them come from Asian countries like India, where Facebook and Youtube are extremely popular. It wouldn’t surprise me if the spammers really apply Youtube logic on this place.
That is, assuming that the spammers are human. I don’t really have an answer in the case of bots.