Sounds like good argument for competition. I haven't heard of a case where a garden club expanded it's power enough to prevent members from leaving and establishing their own.

Garden clubs usually don't have police and armies. They have to bend to powers that do have them, usually the judiciary system, which can summon police. A garden club with police and an army doesn't have to bend to anyone and might force members not to leave.

Depends on the definition of "garden club". Indeed, you probably could call early agriculturists somewhere in Middle East a "garden club".