Standby fees for ground hostess errors! !

We were booked on mango but were just in time because my son fell ill &had been in hospital that same morning. My parents went to check in while I parked. There were NO signs directing the diff passengers to the right queues on the busiest long weekend with all flights to CT fully booked. There was 1 long queue & 1 short & when I found them they were about midway in the long 1 and I asked them if they were in the right queue and my elderly parents rep**** that they think so because there had been no calls for CT since they were standing in this noisy airport in this queue. I then went up to a ground hostess &checked whether that was indeed the right queue since the flight was suppose to take off at 6:30 &they would never board all those passengers by then &she rep**** yes it is &that they running late so we shouldn't worry. We stood in the wrong queue UNTIL the supervisor came around asking where people were headed accompanied by the same ground hostess who then realised she put us in the wrong queue. When I explained that it wasn't our fault that we need standby tickets to tickets sales she had the audacity to cheek me that mango staff are up early for us to check in on time.