@ Shi!
I didn't know that!
Well, I'm not sure since my Portuguese isn't really good, but I think in Brazil "propina" means "bribe" or something that has to do with corruption? Like when someone pays a politician for a favor or something like that.
At least I used to hear the word a lot in in political news reports
actually most of the times I'm glad when they already include the tip in the bill because I seriously have no clue whatsoever of how much I'm supposed to tip and I don't know if asking is really a good idea. But yeah, it really sucks when people expect you to pay a HUGE tip, especially when you're on a low budget.
I know this may sound sort of pathetic, but now, when I'm in countries where I know I'm supposed to tip, I mostly buy food from the supermarket or something like that just to avoid tipping
or I just leave this part to friends and pay back to them later, that experience in Argentina scarred me for life.