If it's anything like San Francisco, once word spreads that a gaming company is shuttering, there's pretty much a "land grab" from the other local companies for talent.
Especially at a company like Zynga, that at least as far as I know, had a fairly rigorous interview process. It's a chance to get a pre-screened engineer, possibly on the cheap.
understandably a company would want to pay less for higher quality work, but at the same time if the process was rigorous and assuming many tech recruiters are also trying to poach the employees - i would think 'on the cheap' wouldn't really apply given supply/demand here
It is on the cheap in the sense that they wouldn't expect to screen such people as much. It obviously isn't free, costs more than hiring from within, but cheaper versus trying to gauge recent graduates and the like.
Every time one of these things happens, I actively see (employed) game-dev buddies on Facebook publicly advertising jobs at their present companies to their newly laid-off friends.
Game developers are still a pretty tight-knit group. It's not like getting laid off from a Wal-Mart.
There are a zillion people trying to get into games. This actually makes it hard to find those who have actually made games. So when a (relatively) known quantity becomes available, there are immediate opportunities.