Concerned on ethics

This weekend I went online to book my flights with Khulula. Since I am a Vitality member with Discovery, I apparently qualified for a 20% discount on my flights. Booked the trips and paid. It cost me about R1051 for a return trip from Durban to Jhb. I also had to book for two of my family members but they are not vitality members. Had to book from Khulula's normal home page. Proceeded to book the exact flights (same date same time) and to my amazement I was surprised that both their tickets only cost me R1951. Totally awe struck as to why my so called discount flights via Vitality costs me more than a normal flight ticket with Khulala. Why is Vitality falsely advertising their discount flights when there is no discount at play?