They are not apes, they are Monkeys.(Barbary Macaques)
They are not aggressive animals, but can be driven to be aggressive by idiotic tourists who touch them, get too close and carry food in rucksacks and plastic bags.
Nobody charges you to enter Gibraltar so can't understand what you wasted your money on. Your adventurous nature probably took you on tour of Matalan, Marks and Spencer, Morrisons and some pharmacy (not that you actually purchased anything)
However you think that the couple of Cartons of B+H or Superkings and that bottle of cheap whisky you bought was money really well spent.
Rather than staying on the ship, some should be staying at home.