DH attends college now and it varies by professor. Of the 7 professors he has had - many of them for multipule classes - only 1 has had a sticking point for being on time. And that is his current professor for his Friday and Saturday morning class. The classes that start in the evening, none of the teachers have had an issue with those adult students that may be arriving late.
DH gets along with the one professor really well and he asked her about this the one day after a couple of the 19-25 year olds complained about their saturday morning professor. She told him, that if he was coming to her classes during the day time hours, she does have a sticking point for getting to class on time. Her stance is, most of the people that take the day time classes, don't work and are not on a tight, juggling work/school schedule. Where as, those in the night classes, most are working adult students, that are on a tight work/school schedule. She used his working schedule as an example. He was working in a city 1 1/2 hour drive away. He got off the clock at 4 and had to be in her class at 6. She understood that if he had no delays, that when he got home at 5:30, he had already put in a 12 hr day. Before heading to class, he would want to change out of his uniform, freshen up, grab a quick snack/bite to eat, before heading to school for another 3.5 hours. While she didn't expect him to come strolling in a 30 - 45 minutes after the class started, 10-15 minutes she didn't have an issue with.
She also said, for those that take a Saturday class, the school offers the time slot, if you as a student choose to take that class during that time frame, you had better make sure your Friday night party life was kept in check, because she has zero leway for those that can't come in on Saturday after they partied all Friday night. If she's giving up her Saturday's to teach, by golly you had better be willing to for go a few months of no Friday night parting to get this class taken and taken seriously.