I agree with Rob, don’t be nice, be an asshole. Look, if anyone gives you a nasty look then you have every right to question why they are late. Now, for me being were I live, I cut her/him some slack due to the weather.
There are sometimes people do get to work late. One time I was waiting at the UPS store, and the person that opened the store was 5 minutes late, running to the door to open it and I wasn’t in a rush. Despite the fact, I was a nice guy. Told her to calm down and take some time because I don’t want get the wrong info just because they need to rus to catch up. (Hahaha, kinda of funny to think about that now, LATE, hmmm like my SUCDVD’s).