I think it's unlikely that SpaceX wasn't aware of the damage that would be caused. They have a pretty good engineering team, and that aspect didn't involve an anomaly, it was the vehicle operating as planned at launch. But admitting the inadequacy of the launch facility would've undoubtedly led to significant delays. Fortunately for SpaceX, the rocket blew up, which will draw media attention away from the damage on and around the launchpad.
Interestingly, this post predicting exactly this kind of damage was flagged on HN just days ago: https://news.ycombinator.com/item?id=35590279
I think it's unlikely that SpaceX wasn't aware of the damage that would be caused. They have a pretty good engineering team, and that aspect didn't involve an anomaly, it was the vehicle operating as planned at launch. But admitting the inadequacy of the launch facility would've undoubtedly led to significant delays. Fortunately for SpaceX, the rocket blew up, which will draw media attention away from the damage on and around the launchpad.