I know it can be a bit irritating at times, but if every topic stuck rigidly to its title then people would skip whole topics that they thought wouldn't interest them.
Many times I've read a topic that didn't particularly interest me at the time, but thought there may be other content in there that I didn't want to miss (I'm the nosy type!), only to find myself actually engrossed in the topic itself.
So, how is the barbie season going then? ...