I had a similar problem with a taxi driver in LV, but my taxi driver was slightly more justified in getting upset at me. As I'm not from the US, I hate tipping, and especially how it's applied inconsistently (why should a taxi driver get a tip and not a bus driver, or a waiter get a tip, but not an air steward, etc) I know they get paid crap, which is disgusting in a country like the USA, but that's a different story. Anyway, I tipped a LV taxi driver around 10-12% (my usual %) and was very upset at me because of the low tip I gave him. I was like FU, I don't have to give you any more, and I didn't.

I also have a question about tipping at buffets in LV and the US in general. Do you need to tip at a buffet in LV or in the US? When I'm in LV, I usualy eat at the cheap buffets like the 777. I don't see any one tipping usually there.

As I've eaten at 777 quite a few times, I recognise a lot of the staff (they don't recognise me as I don't go often enough) so I might give the person that's been the most attentative towards me (removing my plate really) a dollar or two. They always seem genuine when I give them a $ or two.