This is surely an obscure topic, which pretty much only engineers care about, but here goes:

The National Institute of Standards and Technology (NIST, a government agency) develops the Reference Fluid Thermodynamic and Transport Properties Database (REFPROP) which calculates fluid properties for many industrial chemicals. Calculating such properties is critical for all sorts of engineering calculations. NIST charges $200 for this program, which seems very strange to me. If NIST came to the conclusion that such a product has significant enough positive externalities that the government should develop it (which seems relatively plausible to me), why do they charge money for it? Since software has a marginal production cost of zero, shouldn’t NIST’s goal be for people to use it as much as possible? If it were free, students could use it and other developers could use it in their own programs, making it a lot more useful.

NIST also seems to charge for a lot of other software it creates.