As I understand, most tipping occurs socially in lower-paying jobs that require little skill or education.
This assumption might be leading you astray. It's not that waiting tables is a “lower paying” job, certainly not one that requires little skill. And it's not that all people working in the hospitality industry are dirt poor. Rather, the problem is that the law allows restaurants to pay what is effectively a token wage (often not simply relatively low or at the minimal wage but ridiculously low and way below even the regular federal minimal wage) and count on the tips to make up the difference. The comments detail some interesting nuances that depend on the jurisdiction but beyond the details, the thing is that the tips effectively are the pay and there is little you can do individually to change that.
This also means that to be competitive, a restaurant must post prices that are way below what is actually required to run the business and compensate all those involved, because the service is not included. In fact, in some situations you won't even have a choice (e.g. for large groups) and the restaurants will impose a fixed “service charge” on the final bill… on top of the prices printed on the menu. It feels deceptive but that's the reality. So even if the owner-operators of a restaurant without employees have less overhead and get to keep the profit that's left after paying all expenses, you cannot assume that a fair compensation for their work is included in the price.
So am I still expected to tip for the service?
Edit I also noticed that on their receipt, the minimum suggested tip is 10% while many other restaurants have 15% or 18%.
It seems the question has answered itself. Pick the middle suggestion on the receipt (15%?) It doesn't really matter how strongly we may convince ourselves that we know better, looking for a reason to ignore this hint and what everybody else is doing is bound to be obnoxious.
