Mandatory Tipping - Valentines Buffet

Just finding out, is this how restaurants work now? Tipping is mandatory for wait, a buffet??? I'm pretty sure adega isnt a fine dining restaurant, the price of the tip equates to the drinks. It's a buffet, we serve ourselves, even get the plates ourselves. You pay the same price as your drinks to get served your drinks? Sorry just finding out if this is normal that's all... last time I would be supporting this franchise for a buffet, I think it's exploitation of the fact that's valentines day and people aren't shy to spend...

The tip was 10% of the total bill and not just the drinks for which was actually served to us. Not forgetting the exorbitant price per person of R319 for a buffet.