This paper critically investigates the law and economics of competition law enforcement in conflicts between workers and employers in the EU and the US. The conflict between worker solidarity and market competition attracts significant public attention due to the legal conundrum facing precariously employed gig workers. This paper reveals that in light of the strict consumer welfare standard underlying competition rules, competition law has become an overall disciplining mechanism impeding collective worker action beyond the limited case of the gig economy. Using a holistic theoretical framework comprising of neoclassical and Marxist exploitation theories, the paper shows that sound economic analysis justifies resolving the competition–solidarity conflict in favour of solidarity. After showing that the consumer welfare standard overlooks the idiosyncratic qualities of labour as a ‘fictitious’ commodity, the paper offers an original and inclusive ‘citizen welfare’ standard that takes into consideration how anti-competitive behaviour affects workers as well as consumers. As a result, the paper also contributes to the post-2008 debate on whether and how competition law could contribute to equality by shedding light on competition law's treatment of workers and their welfare.