I have it in my contract that I do not do breakfast for children arriving after 7:15 am. I only have a couple kids that start earlier, a few times a month, so I don't have to do it often.
What bugs me is parents who bring their kids later in the morning with half their breakfast in their hands and want them to sit at the table to finish it. I don't have time to put them at the table and watch them eat while I have a bunch of little ones running around in the playroom!
I let them know that they have to get them to finish it before they come.