The conceptual distinctions drawn above between different types of publicly provided
goods provided in kind rather than in cash are not necessarily clearcut in practice.
Evidence on use of certain public services by immigrants might be amenable to
empirical analysis through collection of information from social surveys but for many
aspects of public spending there may be little alternative to making plausible
assumptions about publicness of the service provided in order to delineate a static
picture of the exchequer effect.