pewc_product_show_totals.php

<?php

function demo_pewc_product_show_totals( $show_totals, $post_id ) {
  // Show the Totals fields for product IDs in the array
  $totals = array( 64, 66, 454 );
  if( in_array( $post_id, $totals ) ) {
	  $show_totals = 'total';
  }
  // Hide the Totals fields for product IDs in this array
  if( in_array( $post_id, array( 969, 1111 ) ) ) {
	  $show_totals = 'hide';
  }
  return $show_totals;
}
add_filter( 'pewc_product_show_totals', 'demo_pewc_product_show_totals', 10, 2 );