I have had drop ins from time to time that use the spots, when my p/t aren't here or another f/t is sick or on vacation. They are SAHMs that have an appt and need someone to watch their child for a few hours. I don't ever rely on the $ and look at it as a bonus that week!
I have never had any negative issues with these kids or the parents. The only problem is the kids not wanting to leave and begging their mom to bring them back!