Thats, Not, True.
Sure, real suppressors are an ATF controlled item.
Replica silencers are not real suppressors, and therefore are not covered by the ATF.
In California, there is a specific state law controlling silencers, and they still allow replica silencers.
Wait one...
From Opsec airsoft, Show notes: 03/05/08
FOAM FILLED SUPPRESSORS ARE LEGAL IN CALIFORNIA, AND CALIFORNIA HAS THE MOST RESTRICTIVE GUN CONTROL IN THE COUNTRY (as a state)
FOR THE LOVE OF GOD, STOP PROPAGATING THIS MYTH ABOUT AIRSOFT SUPPRESSORS, IF THEY ARE REPLICAS, THEY A