Fog Light bulb costs 20 times what it should!

I had a fog light bulb fitted to my i10. The service was good and the people friendly. Unfortunately the bulb cost R624.18 which seemed a bit much for a bulb. The box was 'Genuine Parts' and the bulb itself is marked 'Osram' and 'Made in Germany'. I have since found out that I can buy H8 fog light bulbs for R30 online! The same bulb is fitted to many BMWs but I haven't asked them for a price. I think R594 is a lot to pay for a cardboard box.