VSMShadowMap castShadow when receiveShadow enabled

Questions
1

Into file three.module.js (WebGLShadowMap.js) renderer.shadowMap.type = THREE.VSMShadowMap adds castShadow for mesh which have got receiveShadow=true even if mesh castShadow=false. Why is this done?

if ( ( object.castShadow || ( object.receiveShadow && type === VSMShadowMap ) )

White plane castShadow=false, receiveShadow=true

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image823×525 31.1 KB

When deleted is ok || ( object.receiveShadow && type === VSMShadowMap )
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image775×490 29.8 KB

2

As far as I remember this is how the Variance Shadow Map algorithm works.