The only folks who have to worry about insurance, overhead, EPA regs, minimum wage, workers comp, etc are people who have something to loose. Those who do not have much to loose will continue cutting every one else’s price, and since they don't have a damn thing to loose no one is going to spend the time, money, and effort to stop them from doing so. Welcome to our "fair and protected" society where legitimate concerns are at a huge disadvantage to the ones who are less than "legitimate". I AM NOT against a guy doing some side jobs out of his garage, but "half ***" shops bug me.
If it is the shop I think you are talking about, they have a terrible reputation and have been a revolving door of employees and even "Owners". They are also known to be very slow so the end result is the same as the faster guys who charge more.