Someone who doesn't label themselves, especially in relation to political party, philosophy or religion, but could apply to other arenas where someone shuns a particular label. Of course the irony of being an antilabeltarian is that yet another label has been adopted.
A product or product that has a negative utility for the consumer. This term is most often used when considering the costs associated with externalities.
If every person consumed one good every year and shared one antiblago, this would lead to an environmental crisis caused by the overproduction of bads.