Dar gorjeta insuficiente: é pecado no judaísmo?

Judaism rules tipping under minhag hamedinah — the custom of the land — alongside the general dina principle that civil arrangements follow civil norms (Nedarim 28a). So there is no fixed percentage with religious status. But two Jewish values frame the receipt. The first is hakarat hatov, recognizing the good done for you: Joseph's entire story turns on acknowledging benefit, and the sages require gratitude even to an inanimate object (Moses' staff, the sea) — a fortiori to a person who served your meal. The second is the worker-protection tradition: where tips constitute wages (tip-credit systems), halakhic authorities treat undertipping as adjacent to oshek, the oppression of hired workers the Torah forbids — the command applies to Jewish and non-Jewish workers alike (Deuteronomy 24:14's 'hired worker who is poor and needy' is read universally). There is also a distinctly Jewish genre of advice on this: the Chafetz Chaim's code of honesty applies to transactions of any size, and small economies at a worker's expense are exactly where the tradition suspects the yetzer hara hides — stinginess dressed up as principle.