There’s a meditative, soothing quality to it. Playing brushes can assist you in developing better timing and flow (because of circular/elliptical stroke patterns) — which will also show when playing with sticks.
All time great brush players include Papa Jo Jones, Clayton Cameron, and Jeff Hamilton.
Clayton Cameron devotes a segment to the same relationship. The arguments are compelling and valid. However, Mr. Paton cites a deeper source: shoe shine boys who employed their individual rhythms in brushing down their customers with whisk brooms after they shined the shoes. He backs this up with copious citations within the article. He also traces the development and evolution of suitcase drumming in which brushes were used, as well as the importance of barbershops as musical centers of gravity and where some of the whisk broom rhythms were born and evolved. In the latter it appears that Louisiana was particularly important. The irony is the pioneering New Orleans drummers, such as Louis Cottrell, Sr and Baby Dodds eschewed brushes.
If you’ve never tried playing brushes, I encourage you to get a pair and start fooling around with them. You’ve been missing out 😉