Not based on ignorance here, based on experience, real life experience spanning well over 40 years of buying and selling various houses. Looks like I ruffled a few feathers, it happens. Since you used the word ignorance I'll go with naive, not as harsh a word.
Maybe people are lucky or naive I'm not sure, bottom line if a person feels they were treated right that's all that matters. I know quite a few people who moved over the past few years, and not one of them had anything nice to say about their broker, in fact they mention how the broker either played games, lied, or tried to screw them. I almost listed with one and he pulled a trick with the commission and I sent him packing, then we decided to hold off. Are they all bad? No, but I'd say the vast majority are, just like dealerships, contractors, and repair shops. Just look at all the threads on this site to back up the dealership and repair shop problems.