This is absolutely my experience. For example, you'd think that the message passing space is completely owned by FOSS at this point. But, a while back, I worked at a shop that used a commercial library for building APIs, and I was genuinely impressed at how nice it was to work with. It would be difficult or impossible to do a proper analysis on this point, but I wouldn't be at all surprised if that package paid for itself many times over in annual labor cost savings.