One reason why engineers and companies have trouble discussing the job market is that talented people who know how to craft their resumes don't imagine that any other kind of candidate exists.
Unemployed people have lots of time. Understand that and you'll understand why a weekend like this makes sense.
One reason they're unemployed is that they don't know how to demonstrate their value. A lot of engineers are actually poor at communicating, and not that great at resumes.
This weekend was for them.
Ones that are young enough not to know any better. This is a double-win for a company that only wants to hire 22 year olds anyway, as it avoids having to hide under the hazy fog of "culture fit", and they get free work out of the deal to boot.
I'm sure the OP means well, and it may have been a success for them, but I don't know anyone in my circle who would participate in something like this, unless they were utterly desperate for a job. I thought there was a serious talent crunch? Who is courting whom?
I wonder what sort of engineers self-select in a process like this?