Yes, they would be paying for developers' time, and most likely never notice the difference. The value added doesn't automatically translate into a viable mode

Yes, they would be paying for developers' time, and most likely never notice the difference. The value added doesn't automatically translate into a viable model where that money ends up in the library author's hands. Companies sponsor projects for exposure, street cred, or pay for commercial features and support. They will not hand out the realized savings out of goodwill.