At what point do you say that an artist's personal beliefs/behavior/etc become sufficiently obnoxious that you refuse to buy their artwork? I think it is much easier to overlook disagreeable aspects of an artist's personality when you don't interact with them directly - either because they're already dead, or because you are buying through their gallery, and so you don't have to interact with them directly. From an artist's point of view, I think this is probably the single greatest justification for having a gallery - they keep your public at arms length, so they don't piss you off, and you don't lose sales because you piss them off. To me, I think that when buying art, it is still a consumer-based transaction - I expect certain levels of professional, courteous behavior from the person from whom I'm buying it. If it was a gallery that treated me poorly, and the artist is represented by more than one gallery, I'd buy from a different gallery. Just like buying a car - if one dealership has a bad attitude, I'll shop elsewhere the next time I want to buy a car. If I'm dealing directly with the artist, and not going through the gallery, and the artist is rude/obnoxious/abusive, I'll have to seriously question my art budget allocation to their work - after all, art is an entirely discretionary purchase - there's no survival need being met by a photograph on the wall. Do you make a distinction between politics and personal behavior? I think political leanings are a much bigger gray area than demeanor... would you draw the line at racist beliefs? what about membership in the Nazi party? the Communist party? If their artwork does serve to advance their political agenda? If their work is divorced from their agenda?