That could happen too, at least in some states (in others it may be illegal). However, given that these parents believe that puts their child and themselves at

That could happen too, at least in some states (in others it may be illegal). However, given that these parents believe that puts their child and themselves at risk, they'd go far to stop it, up to faking vaccinations - at which point any outbreak would "prove" the vaccines are ineffective. So I don't think there's a way of avoiding a confrontation with the movement itself.