No one really likes competition
Although procurement rules are usually conceived to pursue increased competition via transparency and say non-discrimination, those which benefit from the increased access to procurement contracts coming from the private sector are not really keen in more competition that what is strictly necessary. Particularly, they do not like competition coming xfrom the public sector.
It is no surprise then that in the US private suppliers to the Government are throwing fits of rage with the work being done by 18F (a public agency) to improve procurement practice and procedures within the US Federal Government. It appears lobbyists from industry associations are busy trying to clip 18F's wings as its activity is affecting their profits. Apparently, the problem is not only the work carried out by 18F itself but its role in increasing competition from new private suppliers.
I for, one welcome competition irrespective of its public or private origin.
More details (and a great writeup) here.