Hmm, I dunno, I suppose it's personal preference, I'm surprised you immediately walked out though.
If she's 21, slim, attractive, smiling and looking at me in "that" way then she can call me 'madam' for all I care and I'd still think she was great ... can 'mate' be flirty perhaps? ... no, I guess not. But I'd still go with it.
However, if she was wearing a tracksuit, had a Croydon facelift and looked fresh out of McDonalds, and just grunted 'ere ya go, mate' before storming off with her knuckles dragging behind her then I could see why you were not that impressed.