No doubt many new hires are OK relocating to Menlo Park. Evidently, many are not. Facebook would not invest in an expensive offices in NYC, for instance, if everyone was just happy to relocate to its huge campus in Menlo Park.

My comment referred to the first proper Facebook campus was going to be very close to Palo Alto since that's where their first offices were. Just like has been the case for Google and a bunch of other SV employers.