You ask the right question, but it doesn’t appear that you have looked far enough for your answer. You ask whether the members are authorized to remove directors “by the law or the bylaws,” but you cite only the silence of the bylaws.  In fact, the nonprofit corporation law of your state specifically provides that the members have the right to remove directors unless that power is denied them in the bylaws. Simply stating in the bylaws that the directors also have a right to remove directors, as is also spelled out in the law, does not deprive the members of the authority to take such action as well.  Most, if not all, state nonprofit corporation laws provide a right for members to remove directors on their own initiative.

This goes back to one of my favorite questions: Whose organization is it? (See Ready Reference Page: “The Key Question: Whose Organization Is It?”)  When you have voting members, generally their rights are paramount.

It isn’t clear to me why a theater group needs voting members, who have the ultimate power to control the artistic direction of the organization and the use of its property. You could have contributing or supporting members without their having legal rights of control. But unless you change the structure of your organization, you run the risk of recurring battles like the one you are now facing. 

Your bylaws are not irrelevant. They are just not comprehensive.