/**
 * Hide prices and cart buttons on individual category pages
 */

add_action('woocommerce_after_shop_loop_item_title', 'cc_hide_loop_product_prices', 1);

function cc_hide_loop_product_prices(){
  global $product;

  if(is_product_category(array('category-name1', 'category-name2', 'category-name3'))):

  // Hide prices
  remove_action('woocommerce_after_shop_loop_item_title', 'woocommerce_template_loop_price', 10);

  // Hide add-to-cart buttons
  remove_action('woocommerce_after_shop_loop_item', 'woocommerce_template_loop_add_to_cart');

  endif;
}

/**
 * Hide prices and cart buttons on single product pages
 */
 
add_action('woocommerce_single_product_summary', 'cc_hide_single_product_prices', 1);

function cc_hide_single_product_prices(){
  global $product;

  if( has_term(array(category-name1', 'category-name2', 'category-name3'), 'product_cat', $product->get_id())):

  // Hide prices
  remove_action('woocommerce_single_product_summary', 'woocommerce_template_single_price', 10);

  // Hide add-to-cart buttons
  remove_action('woocommerce_single_product_summary','woocommerce_template_single_add_to_cart', 30);

  endif;
}