Yes, it would be easier for me to bring in a bag for everyone ahead of time. But I believe in giving the students ownership of their learning. By asking them to bring in their own bag I am fostering responsibility and memory skills. Some students even think about others and bring in an extra bag. It never surprises when I see which students do this. It's very endearing.
In the photo above, students are listening to some ground rules. To ensure that students don't get overly excited and started running into one another screaming at the top of their lungs, I set some important boundaries.