I remember studying Danger Areas in Trevor Thom's Air law manual and it covered this very area.
Apart from needing to know this for your PPL theory exams, it does come in handy later on.
If you've got an appreciation for distances based on Lat figures, you'll know if your heading towards or away from a danger area without having to look at a map.
Also, if a danger area is activated through NOTAM, you'll know by it's designated number if it's going to affect your flight plan or pose a hazard - again you won't need to refer to a map.