Pooling resources for some useful purpose is called charity or business partnerships, and done voluntarily.
They certainly provide better outcomes - in case of charity, even where gangsterment doesn't or even worsens outcomes.
Only two gangs pool resources coercively - mafia and gangsterment bureaucracy.
Both are as far as can be from anarchy by definition.
If it's proper for them to coerce money, it's certainly proper for a local charity to threaten putting you in a cage if you don't pay your anarchic "tax" to their outcome improvement cause, and do that if you don't agree to their extortion.