The (paywalled) article states that they attempted to get press passes but were denied, so they snuck in. Perhaps the size of the event meant that YC wanted to

The (paywalled) article states that they attempted to get press passes but were denied, so they snuck in. Perhaps the size of the event meant that YC wanted to limit the number of press? I don't know if they have a reputation for being disruptive, I just found the whole article petty.