We explore the role of a relay in multiuser networks where some physical perturbation shared around the users may generate data traffic for them simultaneously, hence cause their transmission patterns to be correlated. We investigate how the gain from the help of a relay varies with correlations across the users' transmission patterns in a bursty multiple access channel where the users send signals intermittently. As our main results, we show that in most cases a relay can provide a greater degrees-of-freedom (DoF) gain when the users' transmission patterns are more correlated. Furthermore, we demonstrate that the DoF gain can scale with the number of users.