That was my first question too. What "engineer" has $50K sitting around to practically throw away? Then I remember, when it comes to tech reporting, "engineer" could mean anything on the spectrum between "7th code monkey from the left" to "CTO".
I was more commenting that many other people outside the industry are going to become familiar with this idea on a somewhat more visceral level now that it's at the point that CNBC is talking about it.
As an aside, you might be surprised at how many of those "seventh code monkey from the left" are clearing over $200k per year at Amazon. The last time I spoke to people I know at Google/Facebook I was hearing total annual compensation packages of about $250k for senior level in NY and CA.
If you don't have a family and aren't growing your spending habits to match your pocket you can easily have that much extra cash lying around (NB I hesitate to use words like "easily" because people tend to have an indignant reaction, but that doesn't really alter my point).
And he can stop the experiment any time.