Shopping on its own fix the problem when it's the whole system that is at fault.
A Wedgwood sugar bowl from the early 19th century in the Museum of London Docklands is a fine example of the beginnings of fair trade shopping. Inscribed on it is the marketing message: “East India sugar not made by slaves. By six families using East India instead of West India sugar, one less slave is required”. Like so much about so-called ethical consumption, it exposes its own limitations however.