More likely Zuck correctly saw that Google as the incumbent had much more to gain from such a scheme. Facebook wouldn't be where it is today without aggressively poaching employees from Google, in their early acquiring tech chops phase they were basically the inofficial open source arm of Google because they hired so many googlers who wrote near 1-to-1 clones of internal Google tech and later also released them as open source long before Google ever got around to releasing the real thing (buck, thrift, ...). These days of course, Facebook itself is a powerhouse of original tech.
Apparently FB hyper-targeted Google employees with ads based on the profile these employees had happily volunteered when creating their FB profile. (Wish I had a reference link).
Also, from what I understand (again, only hearsay, I don't have any proof for this), there were many employees at Google who thought "Don't be evil" was a joke.
And so they decided they will go to Facebook, which was more closely aligned with their morals, as explained in this rhyme -
> there were many employees at Google who thought "Don't be evil" was a joke.
Well, and the wage theft conspiracy amongst other things proved them right. A smart and experienced CEO like Eric Schmidt would certainly have known that what he was doing was illegal and also that it would be profitable, zero risk to himself and low risk to the company, even if caught. His only possible mistake was to underestimate Facebook as a competitor and the cost of giving them probably more of a leg up than was wise in retrospect by handing them a huge bidding advantage for top tech talent by "defecting" from the collusion. In retrospect it might turn out to have been one of the most expensive rounds of prisoner's dilemma ever played ;)
In a perverse sense, it's a display of markets working effectively. The more big tech players entered into a cartel, the greater the incentive got to defect and pick up talent that wouldn't have been affordable otherwise. That doesn't imply anything noble about the practices of the people who defected, but it's an interesting display of how such things fall apart even without requiring any moral action.
