In conversations with locals on this topic they say they generally don't tip and it isn't expected from them. in addition they are frequently charged less for whatever service/product is being sold. But the service providers do expect and rely on tips from tourists. I pretty much always pay double what is charged for a taxi ride ($20 bz for a $10bz fare) and between 20 & 25% on restaurant tabs. The place I've made an exception to that is spa services. The prices are higher than what I pay in the states, and generally it is the owner providing the service. There I often don't tip at all. That's just my perspective. I think tipping is pretty much a matter of personal choice and the "customs" run from one extreme to another.

I can never remember which is better . . . safe? . . . or sorry?