To demonize a whole industry like that is an unfair statement. Perhaps predatory in certain instances, but no more than any other industry. But to endorse a wholesale dismantling is irresponsible.
So let me explain: if you borrow at 10%, and double the interest, what do you get? Well the critical thing is time, patience, so doubling the interest means allowing half the time to pay back. So in fact the interest is 1.1, not .1, bankers should never add one or subtract one. You take that 1.1 and you square it, that's double the interest, get 1.21. Just as like, the banks take 1.01 international rates and exponentiate them to the 18th power to get 1.2 percent rates, what the market will bear...sort of, haven't borne it very happily recently. Lots of violence.