Integrating a custom post type into a page hierarchy

When Working with pages you can select a parent page and that value is saved as the parent page id number in the child page’s post_parent field in the database.

In your case, you are using a custom post type so you would need to create your own metabox for the parent page; something like:

/* Define the custom box */
add_action('add_meta_boxes', 'child_cpt_add_custom_box');

/* Adds a box to the main column on the custom post type edit screens */
function child_cpt_add_custom_box() {
    add_meta_box('child_cpt', __( 'My child_cpt parent'),'team_member_inner_custom_box','team_member');
}

/* Prints the box content */
function team_member_inner_custom_box() {
    global $post;
    // Use nonce for verification
    wp_nonce_field( plugin_basename(__FILE__), 'team_member_inner_custom_box' );
    echo 'Select the parent page';
    $mypages = get_pages();
    echo '<select name="cpt_parent">';
    foreach($mypages as $page){     
        echo '<option value="'.$page->ID.'"';
        if ($page->ID == $post->post_parent) {echo ' selected';}
        echo '>"'.$page->post_title.'</option>';
    }
    echo '</select>';
}
/* Do something with the data entered */
add_action('wp_insert_post_data', 'myplugin_save_postdata');

/* When the post is saved, saves our custom data */
function myplugin_save_postdata( $data, $postarr ) {
    global $post;
      // verify this came from the our screen and with proper authorization,
      // because save_post can be triggered at other times

      if ( !wp_verify_nonce( $_POST['team_member_inner_custom_box'], plugin_basename(__FILE__) ) )
          return $data;

      // verify if this is an auto save routine. 
      // If it is our form has not been submitted, so we dont want to do anything
      if ( defined('DOING_AUTOSAVE') && DOING_AUTOSAVE ) 
          return $data;
      // OK, we're authenticated: we need to find and save the data

      if ($post->post_type == "team_member")
          $data['post_parent'] = $_POST['cpt_parent'];

     return $data;
}

It has nothing to do with register_post_type. You are tricking WordPress into thinking that it is a child page of another post type (page).