function woo_add_cart_fee() {
    global $woocommerce;
    $items = $woocommerce->cart->get_cart();
    $restaurant = array();
    foreach($items as $item => $values) {
        $restaurant_list_ids = wp_get_post_terms($values['data']->get_id(),'product_cat',array('fields'=>'ids')); // we assumed that restaurant belongs to product_cat
        if($restaurant_list_ids){
            foreach ($restaurant_list_ids as $id) {
                if(!in_array($id, $restaurant)){
                    $restaurant[] = $id;
                }
            }
        }
    }
    $restaurant_multiply = count($restaurant) - 1; // first restaurant id free
    $extra_fee = 2; // 2 euro

    $woocommerce->cart->add_fee( __('Extra fees', 'woocommerce'), $extra_fee*$restaurant_multiply );

}
add_action( 'woocommerce_cart_calculate_fees', 'woo_add_cart_fee' );