It's all about the $$$. You can run any tournament that you want as long as you run a tournament that is open to everyone who wants to compete, i.e. an open tournament. You can run a tournament for left handed Presbyterians named bruce if you think you cna get enough entries to make it work. The women's tournament is feasible because there are enough women who will compete knowing that they have the multiple division format and they do not have to compete against men. There is a seniors tournament that allows the older bowlers to compete agains others on an equal basis. If you added a men's only tournament, you would lose the few women's entries, however you do not gain more men, just subdivide the entries. By percentage how many women are actually cashing versus how many actually enter the event. This just a case of good economics.