You are making an assumption here, that I think is unreasonable: that the pilots (who have probably landed at this airport hundreds of times, it's not like they don't know the place) were expecting a large piece of reinforced concrete to be in the path of the plane.

I'm speculating, of course, but pilots made the decision to land there (albeit in a very short amount of time). They probably made the reasonable assumption that they could "safely" (as safe as it can be, of course) overshoot the runway in that direction. They were certainly not expecting to hit a concrete structure that would pulverize their plane.

Having large concrete structures near airports is not unreasonable, hiding them absolutely is. If instead of a hidden piece of concrete it had been a terminal like in SFO, a sea wall, or another known hazardous structure, the pilots could very well have decided to land somewhere else. Including in the very large body of water next to (or beyond) the runway.

You don't know, I don't know, and we might never know depending on what is uncovered by the investigation.