Employers pay because it's not undifferentiated. It's confidential, and as such, it attracts passive candidates, which no other hiring platform apart from LinkedIn has managed to attract. Additionally, there is no oversupply of good candidates in tech, which is why recruiting spending is so high: it is costly to find them.
That's absolutely right. The problem can be mitigated by focusing on specific roles and locations, though. You don't need that many candidates if your client only hires SWEs in SF. Our approach is to capture a maximum number of companies per vertical before expanding.