Registration costs are similar with US Club or SCYS. That cost covers player insurance and some other member services/benefits (like ODP access or IDP). And each org applies its own rules and restrictions.
Would only make sense to register in both if you intend to play in two leagues in different sanctioning bodies (Jim Hudson 9v9 and CPL Statewide as an example).
Most tournaments are 'OPEN' that can accept teams form either, but not all.
