The fact that it's dark and silent is relatively unsurprising. True, Ienzo is used to people being up at unusual hours, but that doesn't mean he's entirely unaware of how things usually happen. All the same, he agrees with Lexaeus' opinion of the lack of security. Even if the library isn't seen as anything particularly special, scrolls are vulnerable to any of a number of things and someone really ought to be on hand to take care of that.

Even if it will make their task easier to not run into anyone.