> If they give it away for free, that benefits a relatively few people who can make use of it.

If there are relatively few people who benefit the sales will also be meaningless. You'll also have a bunch of losses for things that didn't sell well, liability for when something goes wrong, etc etc. The government isn't a business, it should not try to be one.

Well yeah, but there's a difference between "Let's list all this stuff we've already done for our own purposes and see if we can recoup a little cash" and acting like a business. As long as they aren't putting too much effort into sales, it probably works out to an easy net positive.

The main motivation of this sort of technology transfer program isn't the license revenue itself. That's insignificant when compared to their operating budget. The point of this program is to provide evidence that the research has commercial applications. With this evidence, they are able to go to Congress and show their research helps the economy, which is used as part of the justification of their research budget.