This exists throughout government procurement and it is part of the reason list prices are so high.

The overhead of selling to the government is significantly higher than selling to private companies. So the government simultaneously demands the lowest price while having a much higher cost of sales that needs to be covered by that price. A price that would cover the cost of selling to the government would be non-competitive if selling it to a private company because you may be competing with other companies that don't have to anchor their prices to the cost of doing business with the government.

To work around this companies post a very high list price, no lower than what they charge the government as required by MFN regulations. They then effectively steeply discount those prices when selling to other entities via various mechanisms to more accurately reflect the lower cost of sales. The list price is a fiction required to satisfy "most favored nation" pricing laws, no one is expected to pay it.

tl;dr: In many cases the basic economics requires the government to be charged more than average because they are expensive customers with high overhead. MFN regulations don't make this reality go away so companies have to creatively structure their pricing to satisfy regulations without requiring non-government customers to pay for government overhead.