For folks in our industry that are not using our software (they are using of the closed-source competitors) we are able to show alternatives and still have conversations with operations folks about methods, ideas and other non-technical methods for businesss-process-automation.
We've also got a segment of customers, they are paying us maintainers to basically do the install and a crash-course for the in-house development teams.
We've even been able to work with some groups who "just wanted to prototype some ideas around our platform" -- which sounded like custom-development right? So, naturally we just bill for the time -- like regular old consulting business. Because our core offering is FOSS we've had a few folks push back "I thought the software was free". Oh it is...however, our time spent with you at your behest is not.
Oddly, I've found some other FOSS projects that I wanted to get some help with -- and led with "I'll pay you to pair-program with me for like four hours and answer my dumb questions" -- I was surprised to be turned down: "we don't want to make this commercial, just file a bug" -- do you want a new bug or do you want $800?
Sometimes it's tough to get folk to understand that our FOSS thing needs money to survive and that free-software is not the same as free-consulting. And another side is that some FOSS folk are actively pushing money away.