Provide a better example for hook_commerce_product_type_info()

function hook_commerce_product_type_info() {
  // Return the product types defined in the database by the Product UI module.
  return db_query('SELECT * FROM {commerce_product_type}')->fetchAllAssoc('type', PDO::FETCH_ASSOC);
}

No module is going to want to do that. This should show the actual array you should return.