Some numbers I saw going around yesterday that were looking at the discovered Bitcoin addresses totaled around $18,000.
So I bet their plan was to infect as many as possible over the weekend, and see money roll in come Monday once the Business Decision makers are in play and IT has had time to say "Yea our backups are fucked so we either pay or lose all data"
Lots of money might pour in on Monday as those infected decide that paying the ransom maximizes business continuity.
Already has, twice
Depends on where they live. For most people on Earth this is a very large sum of money that will go a long way (just not 'here' in the countries where the virus spread).