The argument is that being able to control the data rates for different types of content, choking the pipeline forindividualusers or at particular times, will allow allocation of bandwidth to more urgent applications.
Otherwise, society incurs significant transaction costs forindividualusers trying to determine their rights to interact with Internet-connected chattel, and overly protective legal doctrines create border cases where users engaged in socially beneficially conduct nevertheless unintentionally commit legal violations.