Not that bizarre, actually.

For instance, they might had a new project in mind when they started the recruitment process and then didn't get the project.

This has actually happened to me in the past. The guys called me back saying "we'd really like to hire you, but it won't be possible for us right now, because we didn't get the project we were expecting".

(incidentally, they later on got the project and hired me, just four months later; I'm currently happily working there, er, here)