What did you learn? You pretty much accused the guy of stealing your money to use interest free, knocked his whole business model, holding yourself up as a paragon of business virtue while really doing nothing more than whining about a situation you put yourself in and willingly participated in. Then act surprised when others see this, quite correctly, as attacking the guy. Well, that is what you did.
I continue to be amused by people who have one standard for themselves, indeed a whole set of definitions of words held just for their own use, and another quite different set for everyone else.
Not. Amused, I mean. That was mockery.