Why did the cotton brokers of Liverpool insist on persisting with conducting their trade in public and in the open air long after they had premises custom built for that very purpose? What led those same brokers to engage in the riotous melee that became known as the great snowball fight of 1854? And what, if anything, connects these events and practices? Drawing on a range of sources, working in a micro-historical vein and taking oblique inspiration from the social histories of E.P. Thompson and Natalie Zemon Davis, this paper will argue that these events and practices represented the assertion of customs held in common by brokers. In particular, through the insistence on public, open-air trading the brokers asserted a claim to a position central to both the city and its economy – and to the future of both. They were harbingers of future financialization, but advanced their cause through the use of traditions of public assembly, displacing the moral economy of the eighteenth-century crowd.