The majority of HN submissions that were to a referly link were from the founders, I assume the sort-of spammy nature is something they're afforded permission to engage in because they're a part of YC.
Although, I've usually seen those types articles flagged off the front page, so it self-corrects. I don't think there's a bias in favor of YC founders.
There's another YC startup whose founders are more blatant, but their spammy posts are flagged even faster.
