Because they are expensive and very low current and capacity. That means they are limited in how long they will work or how much power they will provide. Technically they have what is called a high output impedance which exacerbates the sort of problems you are seeing.
Thanks, that's good to know.
I believe you misinterpreted my questions as coming off as a know-it-all; I never intended to argue your answers, but learn more about the problem by asking about them. You instead immediately passive aggressively block me out, and preemptively conclude that I'm not willing to learn; not a nice welcome to someone who is new to all this.