Thinking About Spam

Here I am, about to empty my email spam folder and I'm reading all of the titles and sender names. I think to myself, "who writes these? who are these people?" I don't mean like "who are the ass-hats that spend all day sending me junk." I want to know who pics spam email topics and how or why.

Let me go down the list of my spam folder front page. Topics include:
Credit Score
Cable Tv
Free phone (AT&T)
Medicare
Payday Advance
Dating Site
There's a hilarious one from "Ameritrade" so, stocks
Younger Skin
Lasik surgery
Oil change
(my spam mail is suspiciously void of promises about my dingaling)

While I'm really flattered (or offended?) that Cindy Crawford personally wants me to have younger looking skin, I'm still left to wonder why these are spam topics. To me, the ones with a higher probability of a click-through are the ones that scan my address book for familiar names then have an email that looks like a youtube link that just says "Hey, check this out." I am not going to click on an unsolicited email link for an oil change coupon.

Who does? Old people? Their the primary target of online scams because they're easier to scam less tech savvy, so it makes sense.

But I wonder, do spammers to demographic research and have target audiences just as much as a regular marketing team? Why wouldn't they? They are a business and have a product to sell. Is it all done by bots? Or like, one dude in his basement? Are they hiring? I bet I could author some pretty great spam mails.

I'll bet there is a book or article someplace that could describe to me how the internet works.