The peculiar case of the conference spammers
With most spammers, it's pretty easy to see what they're spamming, that is to say what they expect to get out of their spam; what their product or their scam or their cause is. But sometimes I run into spammers, even persistent spammers, where I can't figure out why they're spamming, what benefit they expect to get out of it.
One such persistent case is what I will call the 'conference spammers', who keep sending us email for various obscure-sounding academic conferences (generally computer science ones), usually taking place in remote corners of the world. Some of these at least claim participation by real scientists, but often they have chairs, organizing committees, and so on composed entirely of people from places or organizations that at least do not sound entirely reputable.
(Note that I am perhaps too twitchy about alleged organizations with obscure names, since serious spammers love to invent them in order to make their spam sound more authoritative.)
However, there is no obvious attempt to extract money from you in the email; no conference paper submission fees (but if accepted, your paper will be listed in these prestigious sounding journal indexes), no fee to reserve your place, no nothing like that. No discussion of money at all, in fact. All of which leaves me pretty mystified about what the actual benefit is. My best guess is that it is a bad attempt to pump up the importance of everything associated with the conference by increasing the attendance.
(Since these are academic conferences, I don't think that anyone is making a profit from the registration fees. I could be wrong.)