Hi, I'm disabled although I'm still working (at the moment, may break further). I agree with you.
The biggest issue to consider for any company hiring a significantly disabled person, whether mentally, physically, or both, is they'll be less productive and may require much more oversight, meaning they contribute less to the company. This is the justification behind the lower pay. It makes sense if you're a shit sack capitalist that values production above anything else.
With that being said, Goodwill is absolutely taking advantage of the disabled. They're ostensibly a non-profit charity that exists to provide employment, leading to training and work experience, to the disabled community. They pay their disabled employees the lowest amount possible, actively working to justify low pay. Imagine if your employer was constantly looking to drop your salary so you had to constantly fight them over it. Now pretend you have a significant TBI or are developmentally disabled (just imagine your mental capacity while drunk, but without the feeling good) and still having to fight that. Welcome working for Goodwill.
Fuck Goodwill right in their "charity" hole.
I recall taking a date to the lab I was working in as a grad student and realizing after we got there that none of it is terribly impressive if you don't know what any of it does. She was unimpressed despite my excitement about all of it.
I later married a different woman who actually was excited about our lab things despite not being a scientist and having no idea what our many beige boxes do.