Most large clothing companies in my view are corporations with money-interest and thus corrupt interest at this point. It's difficult not to give money to the shareholders, so I prefer to keep my consumption low, that's probably the best way to hurt their interests which relate to consumerism. Here in Europe we have some Nationalist brands (Thor Steinar, etc), but I find these to be somewhat of a double edged sword because you can become a target. That being said, I obviously avoid any brand literally created by a corrupt businessmen because I just can't stand having the name of them on my clothing. Tiny Rowland & Asil Nadir & 
Philip Green comes to mind.