ya most roos do it and as entertaining as it is for us to see... it does serve a purpose! He is showing the hens where to lay... my roo will often do this when one of my girls is "complaining" that she has to lay!!
All good roosters make sure their women know where the best nests are. I find my Delaware, Isaac, in a nest every day, calling the girls over. Even, on occasion, big old Suede gets into a nest-no idea how he fits in there, but they want to make sure their women are laying eggs to continue their lines, I guess.
My EE roos do it from time to time. Seems to really attract some of the ladies. One of my black sex links in particular really loves it when the boys pick out the nest for her (she coos away in response as she joins him in the box) and my BR hen is generally interested too. I think it's very romantic.