There's a lot of issues with it. It's de facto bribery to buy votes from labor unions. If a union can win the job in a free and open auction then so be it. But it shouldn't be awarded to them just because.
There's a reason we have transparency in the bidding process for government work. This is cronyism.
Not to downplay your observations but thats mostly anecdotal.
Also, I think professionals working in STEM fields should be careful not to encourage this race-to-the-bottom wage-wise for workers, for it may also happen to us sooner than we may hope.