Young earth Creationists are sometimes accused of believing that the whole Bible should be taken 'literally'. What we actually encourage is that the Biblical text should be taken according to the style of writing, that is—taken straightforwardly.
The Bible contains: Poetry, Parables, Prophecy, Apocalyptical writing and Historical narrative. Each writing style should taken as it is written. For example, we should not twist the parables of Jesus to suggest that they refer to real people or events.
Since Genesis was clearly written as historical narrative to understand it straightforwardly means taking it as a literal, historical record of what actually happened.