It does, but remember, they've only been under punishment for around 2 weeks, and they did bring it upon themselves.  Severus is being somewhat lenient by allowing the boys to use their IOU's to mitigate their sentence.  Yes, they are learning how to get along, but then that is the whole purpose of this punishment. They are also learning useful life lessons, like consequences for actions, how to appreciate how easy magic makes things, like laundry ( I wish I had magic to clean my house after a hard day at work!), and how to use different ingredients in potions and brew more advanced drafs than on their syllabus at school, plus how to cook.  Trust me, Draco and Harry know exactly why they're being punished, Sev reminds them every day. As for letting them off, Sev can't do that, he has to be consistent.  Although there may come a time when he considers it due to someone's influence. I won't mention any more about it now, you'll see what I mean later.

Yeah, it's good not to have to wait, I agree.