When you sell to government agencies, it pays to keep the retail price high, because they are spending somebody else's money.
Sort of like the $700 hammer, or $500 toilet seat.
First off, the government doesn't purchase "retail" they purchase at GSA pricing schedules, marked down anywhere between 25-40% for off the shelf items. Items that are specialty items are now firm fixed price units.
Secondly, the megabuck toilet seat or hammer while it makes for great TV stories, doesn't really pan out when you find out what was required for the solicitation required.
I've seen the $500 hammer and at first glance appeared like what you could purchase at a big box store. It had to be made of a special alloy with a handle of ash wood with a moisture content of ___%.
Why the contract was written the way it was, I have no idea, but the RFQ went thru many hands before being released to the street.
As for Surefires pricing structure, yep they're high, but keeping the design so that there is interchangeability isn't as easy as it seems.
Take a look at the Federal Register, find something you're interested in and pull the request for quote specs. You'll find it isn't as easy as it sounds to provide what they want with the documentation demanded to the the Eagle stamp so you can get paid.