(The other reason I take attendance is so that I can recognize at least most of them by mid-semester, so can call on them by name when they raise their hand.)
And I'm often torn with taking points off for submitting work late. On one hand, why should it matter exactly when they submitted the work, if it's good work? On the other hand, I know that if I just said that there's no late penalty, some significant fraction of the students would wait till the end of the semester, then realize that they haven't been keeping up, then create headaches for everyone involved, including themselves.