As a school owner (non-ATA), I'll share some insider things from the industry. Some of the leaders of the ATA market their business plans among the trade journals because they do have great financial results. Their viewpoint on the student is not one I would be comfortble with and if I were a perspective student, I would not want to be training in an organization that viewed me or my family that way. Their viewpoint is that everyone is going to quit anyways, so get as much cash up front as you can while they are excited. Upgrade their program (Black Belt Club, Leadership team, ect.) not based on merit (which if done on merit and earned over time is something I see as positive), but just as a sales hook for someone that they never intend to stay anyhow. As a former bodybuilder, you might be familiar with the marketing and sales strategies of many of the old health spa (Vic Tanny, Jack LaLaine, Grecian, Cosmopolitan, ect) chains. This is just this rip off strategy applied to martial arts. IMO, this not only hurts the students, but over time the publics perception of the industry as a whole. Also, if they are teaching a supplementary program like submission grappling, the ATA (as an org., not all the individual instructors) have that program as an income maker, not to make the student competent at grappling. I have always viewed the heiarchy for an instructor/school owner as the student is first; the school second; the staff is third; and myself fourth. I try to live up to using that as my guide. The ATA leaders who market their business plans to other schools state a very different philosophy.
The ATA is also infamous for their low training and testing standards as an organzation. They have taken some steps to upgrade this somewhat over the last few years. Like any org., there are going to be certain individuals who rise above and demand far more from themselves and of their students than the set standards of their org. I have met a few very good martial artists from the ATA over the years, but overall their quality is pretty low. This is one reason that they try to keep their students isolated and away from the rest of the MA community. It's easier to grow mushrooms that way; keep them in the dark and feed them manure.
You mentioned that they must be pretty good since they were financially successful, but their success is not based on quality. It's based on providing the market with what a large percentage of it wants and also on high turnover (though you've often already paid for it). To many parents, they want their kids to "achieve" a black belt, but neither their kids or the parents want to make too much of an investment in time or effort. With the ATA, this market niche is filled. They offer black belts in 12-18 months with little effort, sweat or growth neccesary (at least under org. requirements prior to their reforms). There is a significant part of the market that "want that belt" in 1/3 to1/4 of the time and far less effort, because they are far more interested in the belt than the personal growth, fitness and fighting skills that it is supposed to represent. Moms don't like their kids getting banged up, so their is very little contact. Adults have to go to work tommorow and don't want a black eye at a sales meeting, so the ATA handles this part of the niche as well. I am all in favor of safety for the students and building them up gradually towards higher contact, but you've got to take them up eventually. Flag football may be fine at one point, but if it was being played at the varsity level in high school, there would be a problem. Let alone a NFL flag team.