I find the fact that tipping is expected very frustrating, and a problem with American culture and the way we compensate service workers (and don't get me started on sick leave and health insurance). But as someone who worked in those minimum wage jobs in the past and now is reasonably comfortable financially, I think giving 3 or 5 dollars to someone who is working very hard for not much money a good use of my funds. I don't if the service is terrible, but I spend more than that on stupid stuff every day. I try not to overthink it. If I'm wondering whether to tip, I tip, at least in the US.