The similarities between this post and the actions that Google and Apple took and are now being investigated for are striking. At a small scale, it's just "good business" not to poach. At a large scale it's "evil" and illegal. Seems rather arbitrary to me.
It's not arbitrary at all. At a small scale, the activity has little impact on the market for labor. At the large scale, it has a very substantial impact.
But you can't really hold it against companies that are poaching. Whether or not they are friends with you because everyone in tech basically knows each other (through networks).
There seems to be a limited talent pool in specific skill sets for certain geographies. In this case, the market is in the favor of the employee, not necessarily the employer.