Yes. Very likely that they can't get a better job. As the previous comment said, they are trained from scratch having no experience in tech whatsoever and mainframe is not remarketable to a web company.
The hardest part of Google is to be accepted for an interview, which they won't.
The second hardest is to actually answer the questions in the interview, at that they don't stand a chance. Don't overestimate a guy who is doing a job reorientation from a random degree, having barely touched a computer before.
Last but not least, Google is only in a handful of locations in the World, banks are more common.
The trick to get your interview at Google is to get somebody to refer you. (And that's not that hard. If you can't find a Googler in person at a meetup, hang out online and write to a few random Googlers. They get a hiring bonus, so if you provide them with the information they need (it's a small questionnaire about you they have to answer plus your CV), lots of them are happy to refer you.)
The interview is a bit peculiar, and not all that correlated to what even Googlers do on their day job, but it's trainable, and you can repeat every year.
Do Facebook at the same cadence, but six month out of phase, and you got a steady stream of interviews. Add eg Microsoft and some other companies, and you are virtually guaranteed to land a decent job at some time. And that holds even after I agree with your caution about overestimating a random but intelligent person. It is quite the time commitment, though.
The locations weren't too much of a problem for me. But I do have to admit that when I joined my preferred location of Singapore didn't really have any engineers, so I settled for Sydney. And as your comment suggests, yes, I was working for a bank in Singapore before.
Yes, it's good advice, I know how this works. Meetups and linkedin messages.
You still need to be in a google location to come across a meetup (there are only so few offices in the world) and your profile might need to be better than "I dropped from art school last month. I like computers."
