This is not a sustainable practice, as now we have larger companies piggybacking off of this existing work, making literal billions, while not truly contributing back.
Heartbleed comes to mind. Two people working on this software, that larger entities used to attain literal billions, was an essential portion of their business practices, and they got nothing.
Sure, their situation has improved, but how many others are out there? This situation needs to change. FLOSS needs resources to maintain itself.