Why XmlSchemaSet explicitely sets targetNamespace to chameleon schemas

<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="test" targetNamespace="test">
    <xsd:include schemaLocation="b.xsd" />
</xsd:schema>`

<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema">
    <xsd:simpleType name="testType">
        <xsd:restriction base="xsd:string">
            <xsd:enumeration value="test"/>
        </xsd:restriction>
    </xsd:simpleType>
    <xsd:element name="test" type="testType"/>
</xsd:schema>

XmlSchemaSet schemaSet = new XmlSchemaSet();
schemaSet.Add(null, @"a.xsd");

foreach (XmlSchema schema in schemaSet.Schemas())  // foreach is used to simplify the example
{
    Console.WriteLine("Target namespace: "schema.TargetNamespace);  // "Target namespace: test"
    XmlSchemaInclude include = (XmlSchemaInclude)schema.Includes[0];
    Console.WriteLine("Include target namespace: " + include.Schema.TargetNamespace); // "Include target namespace: test"
}