Is casual teaching just babysitting in Secondary School?

So basically I have just started casual teaching this year but had a number of years as an SLSO prior to this. I’ve been told that casual teaching is essentially babysitting with casuals marking the role then facilitating the work left by their teachers.

In my experience, I’ve noticed virtually all the work left has been independent tasks, especially from Year 9-12 and there isn’t really much for me to do. I circle the room and check to see if they’re on task etc. All the standard stuff. I just find it boring and not overly stimulating at times and was wondering how do others manage this. I would like to enjoy my casual days more.