Why would Ferrovial, a massive construction company, not be in favour of building a new airport? Even if they only built one runway and one terminal, it would net them many millions.
Oh no, just because you build something big, by NO means you make anything from it.
Just one of many examples, the building of the Millennium Stadium in Cardiff effectively bankrupted the long-established "massive construction company" who had done it (well, it was sold for £1, which is the same thing).