“Some products are termed ‘bads’ because consumption of the product tends to decrease with increasing wealth. Spam is one example of a bad, while beef tenderloin is generally thought to be a good.” Donald S. Chisum et al., Principles of Patent Law 54 (1998).
bads
bads, n. Slang. In economics, the counterpart of “goods,” characterized by a negative correlation between the amount consumed and the consumer’s wealth; specif., the kinds of products that tend to be bought only by poor people.