That's a risk of doing business. AirBnB and Uber are running similar risks against the political system (probably worse - they don't have ~half of the political system in their corner). Every other business is always risking that nobody will buy their product. Having any kind of promise of a guaranteed sale is a pretty luxurious position for any business.

If the risk is large enough that nobody takes it, then the procurement office can look at sweetening the deal (perhaps by increasing the payment per transaction, perhaps by offering some compensation for good faith effort if the legislation is revoked).

There is enormous overhead in bidding on and winning a government project. They're the reason the "37signals" of the world isn't doing them even even though they could probably execute much better on them.