If they admit that airsoft can cause bodily harm they can't classify them as replicas.
"This fact sheet is of interest to you if you have any device that:
* Looks exactly (or almost exactly) like a firearm, but is not a firearm; and,
* Cannot discharge projectiles at all, or discharge only harmless projectiles.
Devices that discharge projectiles that can cause serious bodily injury, such as the penetration of an eye, are not replicas."
Read Stephen Taylor here
Those who trade liberty for safety will ultimately deprive themselves of both.