How do they do this? Spam/email account question

Factual Questions
1

I have an older Kindle for sale on craigslist.
I get an email from “maryjones” at gmail asking hey do you still have this.
I respond yes I do.
I get an instant reply; my email time stamp has my response and the reply both at 7:40 pm. The reply is your typical spam bullshit from some Godly person who is out of town but will arrange for his shipper to come to my house with a cheque once I provide him with a raft of information blah blah.
Then I notice that my reply to “maryjones” is logged as a reply to a completely different email address. :confused:

How does this happen? I get that it’s some sort of automated scam, but why did the first inquiry come under one email address while the subsequent spammy thing come from a different email address? And how, when I hit reply, my email log shows the reply going to a completely different email address?

Bonus question: how on earth do people who own and use computers get taken by such utterly blatant scams? I assume they work with some people because craigslist generates so much of this fraud. And anyone who posts on craigslist has to wade through warnings in bright red letters and all caps and !!1!!!1!! about how to spot such scams.

2

  1. You can set up a “reply-to” address in the email so the reply goes to a different address than the “from” address. Most mail clients have this capability.

  2. Most mail clients also have an auto reply (often called a “vacation message”) that replies as soon as an email is received.

  3. There’s a sucker born every minute, and the Internet makes them easy to reach.