Consider, for a moment, licensing in terms of the question, "How will you pay me?" The GPL is a license that explains to other people that I want to be paid with information, and it doesn't prevent me from also asking to be paid with money. The BSD is a license that enables me to ask a person to pay me with information or money, but it generously does not require either. A proprietary license enables me to just ask for the money.
Regardless of whether or not a person thinks that OSS will naturally prove its superiority to closed, proprietary software, that person must ask themself, "How do I want to be paid?"