A lot of people do consume high levels of refined carbs, and it is unrealistic to expect everyone to be able to abstain from them completely. After all, the best type of diet is one that you can stick to and sustain.
So, the % represents a daily maximum, as opposed to a target to try and hit; this is why our reports state to consume a "maximum of 10%" refined carbs. How much a person's daily maximum is will be affected by certain genes - some people can get away with having a bit more should they wish, whilst others should be stricter.
There certainly is no requirement for people to consume refined carbs should they not want to.