I think everyone hates actual fraud. Many of us are frustrated by those who seem to think they are teaching something effective, but apparently are not (when viewed through an informed eye).
But there are groups of arts that don't fall into either of those categories, which are also not much use for self-defense. I've met people who trained entirely for soft competition (not hard-contact stuff) who had no illusion that their training was all that effective for combat. I've met people who didn't seem to care whether they were learning something for defensive use or not, because it was fun and/or cool. And those folks were all being served well by their schools. To them, it was another alternative to choose from, like gymnastics or football.
Martial arts. Yes, it's kind of like a venn diagram.
Some arts are sport. Some are war.
Some are amusing diversions.
Some are religious, and/or political.
Some are philosophical.
Some are practical.
Some are art.
Sport: win or lose mentality but just a game.
War: life or death mentality, it's about survival.
Entertainment: this is fun, don't let it get boring mindset.
Religious: any of the following: aikido, chi balls, 0 falsability, assertions taken whole without a gain of salt. Personal development.
Philosophical... it about the "DO"
Practical... it's about the "Jutsu"
Art: it's not just a potentially dangerous dance... it's esthetically pleasing and even beautiful.
They don't have to be mutually exclusive. The Art doesn't stand alone.... the practitioner can bring his/her own influence into the expression and experience of the art.