As someone pointed out earlier, you're getting het up about losing a pocketful of small change while behind your back someone empties your bank accounts. At the last estimate I heard for completion of the sorry stub that's left of HS2 (about £60 billion), £100 million represents 0.17% of the cost. The problem is the other 99.83%, £59,900,000,000 or so. HS2 are happily pushing this news because "little people" can understand the small number (a little hospital!), whereas the big number is just , well, benumbing.
The real problem is that central agencies have become so hollowed out of any sort of specialist expertise- they only recruit MBAs- that the consultants and contractors can tell them what they will be pleased to do, and how much they will be pleased to accept for it.