I laugh at the argment that supressors are soooo useful to assasins. They're completely unnecesary for that use.
Seriously, shoot a gun in your house. No one will call the cops, no one will come knock on your door. The sound can't leave your house, cross the yard, enter another, and still be louder than their TV. And even if the gunshot was outside, one shot would at most get a glance toward the street.
But, there's something much more insidious in these lies. It slowly convinces people that they should be banned, then that they are banned, and eventually they are banned, and by then no one knows the difference.