Woah only 9 million , , that is a bargain and certainly a lot cheaper than the alternative. I thought MS would have charged military prices.

Interestingly, in 2011 they were still using MS-DOS:

https://en.wikipedia.org/wiki/File:US_Navy_110129-N-7676W-15...

...and a lot of (physical) stores still use a DOS-based application for their POS systems, judging by the appearance, although they might not actually be running it on DOS but a later version of Windows.