IMO the cold calls (or, these days, linkedin messages, god help you if you ever give any one of them your number, you'll never want to answer an unknown call again) are a bit insane.
They feel like used car salesmen. Incentives are definitely misaligned with the employee -- from what I understand they're usually paid a percentage of first year salary, so they just want to move as many people as possible for the most money.
Not that candidates don't also benefit from a drive to increase offers, but I get the feeling people are pushed into taking jobs they might otherwise would not have.