Totally true. I've heard "trainers" show people how to do exersizes wrong, eat wrong, and not push themselves.
My wife wanted me to look into becoming a trainer, since I love BB and talking about it, helping people and such. Not wanting to be one of those idiots, I looked into Ace Fitness national accredited school - and it is a fairly cheap course, but takes two years (as it should, I think) to complete and get your degree, but I don't have time for that much study for the end result, which they had a chart for. It showed wages for personal, group, sports medical and such wages for top trainers all over the country and even at the group level, I could't live on it. I made that much as a carpenter.
As T said, you'd want to tell people to do what works, and they just want to pay you to tell them what they want to hear. I couldn't deal with the frustration factor in that, on top of low to mediocre wages.