Yes it does. It's to put in your seat bag on your commute. It's best to have the same tool like a 5mm allen in several different configurations. Just like you have 9 different phillips screwdrivers. I have a few loose 5mm allens and this one
http://www.parktool.com/product/3-way-hex-wrench-aws-1 so you can get some leverage on it.
There are gobs of threads on, "what should I get for my basic shop tools?". A few bike specific tools that get used over and over by folks that like to wrench.. chain tool, bottom bracket tool, cone wrenches, crank puller, chain whip/lock ring tool. YMMV of course.
PS. Do you like the way the bike rides? And maybe use more than 1 lock. I don't really know since I don't lock my bikes up, they might get stolen.