Some people don't contribute to GPL projects because they want to make proprietary forks or object to the rules. Contrariwise, people like me don't contribute t

Some people don't contribute to GPL projects because they want to make proprietary forks or object to the rules. Contrariwise, people like me don't contribute to BSD projects (unless paid well) because I resent subsidizing parasitic vendors. But I've never seen an estimate about how large each of these populations are. Anyone have an idea how big a hit you may take choosing one over the other?