Carer requirement costs traveler $430

Tasmanian Emma Butler was refused boarding a Virgin Blue Airlines flight because she did not have a carer with her. The last minute revealation that a carer was needed cost Butler an extra fare to the tune of $430. The airline says there was a miscommunication. Yes, and an expensive one for Butler.
This story finally shed some light for me on the persistent "a carer is needed for safety" claim so often heard. This airline says the carer is needed to help with a lifejacket, if that's needed. But Butler has a good answer for that argument:
"I don't understand what the fuss was about. I've travelled on my own before with no problems. I don't see why they couldn't have put a lifejacket on me before we left the ground, and surely the cabin crew know how to put on a seatbelt?" (Photo via morgueFile.com)