I associate hackers as a group that startups wants to hire not as having similar philosophies. To me this site is a very successful marketing/recruitment tool and not some indication that YC follows the hacker ethos.

The point is that this represents a coöption of the term hacker by the venture capitalist community -- it's always easier to convince someone to accept less value as recompense for what they produce by convincing them that they are engaged in a noble or even a personally virtuous (see e.g. "guru", "rockstar") pursuit.