I don't see an emotion vs logic dichotomy being applicable here; we just don't process numbers like calculators because the world is messy and everything is a c

I don't see an emotion vs logic dichotomy being applicable here; we just don't process numbers like calculators because the world is messy and everything is a context-dependent guess with imperfect information. If 99.9% of the time I go to a restaurant the number I see is eventually adjusted by sales tax+tip, my mental "value" heuristic is going to be comparing that number to how hungry I am, how soon I think I'm getting the burger, how good I think this place is, etc. If half of restaurants abolished tips I'm sure I would develop the ability to incorporate that into my heuristic. And sure like any heuristic it has its failure modes but in general, if you look at a whole population, those heuristics tend to be pretty astonishingly effective in aggregate.