5 MINUTES LATE FOR CHECK-IN AND THEN 5 HOURS DELAY

I was 5 minutes late for check-in and the lady at the counter told us there is no way they could make an exception for us and we need to go to the service desk and purchase new tickets for the next available flight. Another R1100 and we are good for the next flight that was supposed to be 19h35 after a 5 hours delay we finally got on a flight to Johannesburg. So why did I need to pay extra money for my mistake of being 5 minutes late but if their flight is delayed its fine- I needed to purchase food, cool drinks and were late for work the next day. How come they couldn't just help us out for 5 minutes...37minutes after the flight only took off so they could have made an exception!