If you looked into it I think you'd find that charter providers do not support having a new separate union for teachers that provides all of these "programs and incentives."
Having worked at charter schools... I can tell you that each state runs their charter program a little differently, but generally teachers at charter schools are not union represented.
Each school charter is issued independently of any others and the school design can vary dramatically from one charter to the next, which is actually the point. Some charter schools have long days. Some go year round. Some focus on at-risk youth. Some focus on alternative pedagogy... etc, etc.