Perhaps you don't understand the science behind mask wearing. You don't wear them just for yourself. You wear them to help protect the entire community by slowing the spread. Only a narcissist would knowingly choose not to do something simple that would help everyone around him.
Also, you seem to be misunderstanding
@Zachary. Wearing a mask at BGW is not optional. Going to the park is optional. You can opt out of the mask, by skipping the trip to BGW.
Given the crowds, I don't think they are hurting their business by enforcing health safety standards.